Astrochemistry

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https://en.wikipedia.org/wiki/Astrochemistry

Infographic showing the theorized origin of the chemical elements that make up the human body

Astrochemistry is the study of the abundance and reactions of molecules in the universe, and their interaction with radiation. The discipline is an overlap of astronomy and chemistry. The word "astrochemistry" may be applied to both the Solar System and the interstellar medium. The study of the abundance of elements and isotope ratios in Solar System objects, such as meteorites, is also called cosmochemistry, while the study of interstellar atoms and molecules and their interaction with radiation is sometimes called molecular astrophysics. The formation, atomic and chemical composition, evolution and fate of molecular gas clouds is of special interest, because it is from these clouds that solar systems form.

History

As an offshoot of the disciplines of astronomy and chemistry, the history of astrochemistry is founded upon the shared history of the two fields. The development of advanced observational and experimental spectroscopy has allowed for the detection of an ever-increasing array of molecules within solar systems and the surrounding interstellar medium. In turn, the increasing number of chemicals discovered by advancements in spectroscopy and other technologies have increased the size and scale of the chemical space available for astrochemical study.

History of spectroscopy

Main articles: History of spectroscopy and Astronomical spectroscopy

Observations of solar spectra as performed by Athanasius Kircher (1646), Jan Marek Marci (1648), Robert Boyle (1664), and Francesco Maria Grimaldi (1665) all predated Newton's 1666 work which established the spectral nature of light and resulted in the first spectroscope. Spectroscopy was first used as an astronomical technique in 1802 with the experiments of William Hyde Wollaston, who built a spectrometer to observe the spectral lines present within solar radiation. These spectral lines were later quantified through the work of Joseph von Fraunhofer.

Spectroscopy was first used to distinguish between different materials after the release of Charles Wheatstone's 1835 report that the sparks given off by different metals have distinct emission spectra. This observation was later built upon by Léon Foucault, who demonstrated in 1849 that identical absorption and emission lines result from the same material at different temperatures. An equivalent statement was independently postulated by Anders Jonas Ångström in his 1853 work Optiska Undersökningar, where it was theorized that luminous gases emit rays of light at the same frequencies as light which they may absorb.

This spectroscopic data began to take upon theoretical importance with Johann Balmer's observation that the spectral lines exhibited by samples of hydrogen followed a simple empirical relationship which came to be known as the Balmer Series. This series, a special case of the more general Rydberg Formula developed by Johannes Rydberg in 1888, was created to describe the spectral lines observed for hydrogen. Rydberg's work expanded upon this formula by allowing for the calculation of spectral lines for multiple different chemical elements. The theoretical importance granted to these spectroscopic results was greatly expanded upon the development of quantum mechanics, as the theory allowed for these results to be compared to atomic and molecular emission spectra which had been calculated a priori.

History of astrochemistry

While radio astronomy was developed in the 1930s, it was not until 1937 that any substantial evidence arose for the conclusive identification of an interstellar molecule – up until this point, the only chemical species known to exist in interstellar space were atomic. These findings were confirmed in 1940, when McKellar et al. identified and attributed spectroscopic lines in an as-of-then unidentified radio observation to CH and CN molecules in interstellar space. In the thirty years afterwards, a small selection of other molecules were discovered in interstellar space: the most important being OH, discovered in 1963 and significant as a source of interstellar oxygen, and H₂CO (formaldehyde), discovered in 1969 and significant for being the first observed organic, polyatomic molecule in interstellar space.

The discovery of interstellar formaldehyde – and later, other molecules with potential biological significance, such as water or carbon monoxide – is seen by some as strong supporting evidence for abiogenetic theories of life: specifically, theories which hold that the basic molecular components of life came from extraterrestrial sources. This has prompted a still ongoing search for interstellar molecules which are either of direct biological importance – such as interstellar glycine, discovered in a comet within our solar system in 2009 – or which exhibit biologically relevant properties like chirality – an example of which (propylene oxide) was discovered in 2016 – alongside more basic astrochemical research.

Spectroscopy

Main article: Spectroscopy

One particularly important experimental tool in astrochemistry is spectroscopy through the use of telescopes to measure the absorption and emission of light from molecules and atoms in various environments. By comparing astronomical observations with laboratory measurements, astrochemists can infer the elemental abundances, chemical composition, and temperatures of stars and interstellar clouds. This is possible because ions, atoms, and molecules have characteristic spectra: that is, the absorption and emission of certain wavelengths (colors) of light, often not visible to the human eye. However, these measurements have limitations, with various types of radiation (radio, infrared, visible, ultraviolet etc.) able to detect only certain types of species, depending on the chemical properties of the molecules. Interstellar formaldehyde was the first organic molecule detected in the interstellar medium.

Perhaps the most powerful technique for detection of individual chemical species is radio astronomy, which has resulted in the detection of over a hundred interstellar species, including radicals and ions, and organic (i.e. carbon-based) compounds, such as alcohols, acids, aldehydes, and ketones. One of the most abundant interstellar molecules, and among the easiest to detect with radio waves (due to its strong electric dipole moment), is CO (carbon monoxide). In fact, CO is such a common interstellar molecule that it is used to map out molecular regions. The radio observation of perhaps greatest human interest is the claim of interstellar glycine, the simplest amino acid, but with considerable accompanying controversy. One of the reasons why this detection was controversial is that although radio (and some other methods like rotational spectroscopy) are good for the identification of simple species with large dipole moments, they are less sensitive to more complex molecules, even something relatively small like amino acids.

Moreover, such methods are completely blind to molecules that have no dipole. For example, by far the most common molecule in the universe is H₂ (hydrogen gas, or chemically better said dihydrogen), but it does not have a dipole moment, so it is invisible to radio telescopes. Moreover, such methods cannot detect species that are not in the gas-phase. Since dense molecular clouds are very cold (10 to 50 K [−263.1 to −223.2 °C; −441.7 to −369.7 °F]), most molecules in them (other than dihydrogen) are frozen, i.e. solid. Instead, dihydrogen and these other molecules are detected using other wavelengths of light. Dihydrogen is easily detected in the ultraviolet (UV) and visible ranges from its absorption and emission of light (the hydrogen line). Moreover, most organic compounds absorb and emit light in the infrared (IR) so, for example, the detection of methane in the atmosphere of Mars was achieved using an IR ground-based telescope, NASA's 3-meter Infrared Telescope Facility atop Mauna Kea, Hawaii. NASA's researchers use airborne IR telescope SOFIA and space telescope Spitzer for their observations, researches and scientific operations. Somewhat related to the recent detection of methane in the atmosphere of Mars. Christopher Oze, of the University of Canterbury in New Zealand and his colleagues reported, in June 2012, that measuring the ratio of dihydrogen and methane levels on Mars may help determine the likelihood of life on Mars. According to the scientists, "...low H₂/CH₄ ratios (less than approximately 40) indicate that life is likely present and active." Other scientists have recently reported methods of detecting dihydrogen and methane in extraterrestrial atmospheres.

Infrared astronomy has also revealed that the interstellar medium contains a suite of complex gas-phase carbon compounds called polyaromatic hydrocarbons, often abbreviated PAHs or PACs. These molecules, composed primarily of fused rings of carbon (either neutral or in an ionized state), are said to be the most common class of carbon compound in the Galaxy. They are also the most common class of carbon molecule in meteorites and in cometary and asteroidal dust (cosmic dust). These compounds, as well as the amino acids, nucleobases, and many other compounds in meteorites, carry deuterium and isotopes of carbon, nitrogen, and oxygen that are very rare on Earth, attesting to their extraterrestrial origin. The PAHs are thought to form in hot circumstellar environments (around dying, carbon-rich red giant stars).

Infrared astronomy has also been used to assess the composition of solid materials in the interstellar medium, including silicates, kerogen-like carbon-rich solids, and ices. This is because unlike visible light, which is scattered or absorbed by solid particles, the IR radiation can pass through the microscopic interstellar particles, but in the process there are absorptions at certain wavelengths that are characteristic of the composition of the grains. As above with radio astronomy, there are certain limitations, e.g. N₂ is difficult to detect by either IR or radio astronomy.

Such IR observations have determined that in dense clouds (where there are enough particles to attenuate the destructive UV radiation) thin ice layers coat the microscopic particles, permitting some low-temperature chemistry to occur. Since dihydrogen is by far the most abundant molecule in the universe, the initial chemistry of these ices is determined by the chemistry of the hydrogen. If the hydrogen is atomic, then the H atoms react with available O, C and N atoms, producing "reduced" species like H₂O, CH₄, and NH₃. However, if the hydrogen is molecular and thus not reactive, this permits the heavier atoms to react or remain bonded together, producing CO, CO₂, CN, etc. These mixed-molecular ices are exposed to ultraviolet radiation and cosmic rays, which results in complex radiation-driven chemistry. Lab experiments on the photochemistry of simple interstellar ices have produced amino acids. The similarity between interstellar and cometary ices (as well as comparisons of gas phase compounds) have been invoked as indicators of a connection between interstellar and cometary chemistry. This is somewhat supported by the results of the analysis of the organics from the comet samples returned by the Stardust mission but the minerals also indicated a surprising contribution from high-temperature chemistry in the solar nebula.

Research

Transition from atomic to molecular gas at the border of the Orion molecular cloud

Research is progressing on the way in which interstellar and circumstellar molecules form and interact, e.g. by including non-trivial quantum mechanical phenomena for synthesis pathways on interstellar particles. This research could have a profound impact on our understanding of the suite of molecules that were present in the molecular cloud when our solar system formed, which contributed to the rich carbon chemistry of comets and asteroids and hence the meteorites and interstellar dust particles which fall to the Earth by the ton every day.

The sparseness of interstellar and interplanetary space results in some unusual chemistry, since symmetry-forbidden reactions cannot occur except on the longest of timescales. For this reason, molecules and molecular ions which are unstable on Earth can be highly abundant in space, for example the H₃⁺ ion.

Astrochemistry overlaps with astrophysics and nuclear physics in characterizing the nuclear reactions which occur in stars, as well as the structure of stellar interiors. If a star develops a largely convective envelope, dredge-up events can occur, bringing the products of nuclear burning to the surface. If the star is experiencing significant mass loss, the expelled material may contain molecules whose rotational and vibrational spectral transitions can be observed with radio and infrared telescopes. An interesting example of this is the set of carbon stars with silicate and water-ice outer envelopes. Molecular spectroscopy allows us to see these stars transitioning from an original composition in which oxygen was more abundant than carbon, to a carbon star phase where the carbon produced by helium burning is brought to the surface by deep convection, and dramatically changes the molecular content of the stellar wind.

In October 2011, scientists reported that cosmic dust contains organic matter ("amorphous organic solids with a mixed aromatic-aliphatic structure") that could be created naturally, and rapidly, by stars.

On August 29, 2012, and in a world first, astronomers at Copenhagen University reported the detection of a specific sugar molecule, glycolaldehyde, in a distant star system. The molecule was found around the protostellar binary IRAS 16293-2422, which is located 400 light years from Earth. Glycolaldehyde is needed to form ribonucleic acid, or RNA, which is similar in function to DNA. This finding suggests that complex organic molecules may form in stellar systems prior to the formation of planets, eventually arriving on young planets early in their formation.

In September, 2012, NASA scientists reported that polycyclic aromatic hydrocarbons (PAHs), subjected to interstellar medium (ISM) conditions, are transformed, through hydrogenation, oxygenation and hydroxylation, to more complex organics – "a step along the path toward amino acids and nucleotides, the raw materials of proteins and DNA, respectively". Further, as a result of these transformations, the PAHs lose their spectroscopic signature which could be one of the reasons "for the lack of PAH detection in interstellar ice grains, particularly the outer regions of cold, dense clouds or the upper molecular layers of protoplanetary disks."

In February 2014, NASA announced the creation of an improved spectral database  for tracking polycyclic aromatic hydrocarbons (PAHs) in the universe. According to scientists, more than 20% of the carbon in the universe may be associated with PAHs, possible starting materials for the formation of life. PAHs seem to have been formed shortly after the Big Bang, are widespread throughout the universe, and are associated with new stars and exoplanets.

On August 11, 2014, astronomers released studies, using the Atacama Large Millimeter/Submillimeter Array (ALMA) for the first time, that detailed the distribution of HCN, HNC, H₂CO, and dust inside the comae of comets C/2012 F6 (Lemmon) and C/2012 S1 (ISON).

For the study of the recourses of chemical elements and molecules in the universe is developed the mathematical model of the molecules composition distribution in the interstellar environment on thermodynamic potentials by professor M.Yu. Dolomatov using methods of the probability theory, the mathematical and physical statistics and the equilibrium thermodynamics. Based on this model are estimated the resources of life-related molecules, amino acids and the nitrogenous bases in the interstellar medium. The possibility of the oil hydrocarbons molecules formation is shown. The given calculations confirm Sokolov's and Hoyl's hypotheses about the possibility of the oil hydrocarbons formation in Space. Results are confirmed by data of astrophysical supervision and space researches.

In July 2015, scientists reported that upon the first touchdown of the Philae lander on comet 67/P's surface, measurements by the COSAC and Ptolemy instruments revealed sixteen organic compounds, four of which were seen for the first time on a comet, including acetamide, acetone, methyl isocyanate and propionaldehyde.

In December 2023, astronomers reported the first time discovery, in the plumes of Enceladus, moon of the planet Saturn, of hydrogen cyanide, a possible chemical essential for life as we know it, as well as other organic molecules, some of which are yet to be better identified and understood. According to the researchers, "these [newly discovered] compounds could potentially support extant microbial communities or drive complex organic synthesis leading to the origin of life."

Left-wing politics

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Left-wing_politics

Left-wing politics describes the range of political ideologies that support and seek to achieve social equality and egalitarianism, often in opposition to social hierarchy as a whole or certain social hierarchies. Left-wing politics typically involve a concern for those in society whom its adherents perceive as disadvantaged relative to others as well as a belief that there are unjustified inequalities that need to be reduced or abolished, through radical means that change the nature of the society they are implemented in. According to emeritus professor of economics Barry Clark, supporters of left-wing politics "claim that human development flourishes when individuals engage in cooperative, mutually respectful relations that can thrive only when excessive differences in status, power, and wealth are eliminated."

Within the left–right political spectrum, Left and Right were coined during the French Revolution, referring to the seating arrangement in the French National Assembly. Those who sat on the left generally opposed the Ancien Régime and the Bourbon monarchy and supported the Revolution, the creation of a democratic republic and the secularisation of society while those on the right were supportive of the traditional institutions of the Ancien Régime. Usage of the term Left became more prominent after the restoration of the French monarchy in 1815, when it was applied to the Independents. The word wing was first appended to Left and Right in the late 19th century, usually with disparaging intent, and left-wing was applied to those who were unorthodox in their religious or political views.

Ideologies considered to be left-wing vary greatly depending on the placement along the political spectrum in a given time and place. At the end of the 18th century, upon the founding of the first liberal democracies, the term Left was used to describe liberalism in the United States and republicanism in France, supporting a lesser degree of hierarchical decision-making than the right-wing politics of the traditional conservatives and monarchists. In modern politics, the term Left typically applies to ideologies and movements to the left of classical liberalism, supporting some degree of democracy in the economic sphere. Today, ideologies such as social liberalism and social democracy are considered to be centre-left, while the Left is typically reserved for movements more critical of capitalism, including the labour movement, socialism, anarchism, communism, Marxism, and syndicalism, each of which rose to prominence in the 19th and 20th centuries. In addition, the term left-wing has also been applied to a broad range of culturally liberal social movements, including the civil rights movement, feminist movement, LGBT rights movement, abortion-rights movements, multiculturalism, anti-war movement, and environmental movement, as well as a wide range of political parties.

Positions

The following positions are typically associated with left-wing politics.

Economics

See also: Anarchist economics, Comparison of Marxian and Keynesian economics, and Socialist economics

Left-leaning economic beliefs range from Keynesian economics and the welfare state through industrial democracy and the social market to the nationalization of the economy and central planning, to the anarcho-syndicalist advocacy of a council-based and self-managed anarchist communism. During the Industrial Revolution, leftists supported trade unions. At the beginning of the 20th century, many leftists advocated strong government intervention in the economy. Leftists continue to criticize the perceived exploitative nature of globalization, the "race to the bottom" and unjust lay-offs and exploitation of workers. In the last quarter of the 20th century, the belief that the government (ruling in accordance with the interests of the people) ought to be directly involved in the day-to-day workings of an economy declined in popularity amongst the centre-left, especially social democrats who adopted the Third Way. Left-wing politics are typically associated with popular or state control of major political and economic institutions.

Other leftists believe in Marxian economics, named after the economic theories of Karl Marx. Some distinguish Marx's economic theories from his political philosophy, arguing that Marx's approach to understanding the economy is independent of his advocacy of revolutionary socialism or his belief in the inevitability of a proletarian revolution. Marxian economics do not exclusively rely on Marx and draw from a range of Marxist and non-Marxist sources. The dictatorship of the proletariat and workers' state are terms used by some Marxists, particularly Leninists and Marxist–Leninists, to describe what they see as a temporary state between the capitalist state of affairs and a communist society. Marx defined the proletariat as salaried workers, in contrast to the lumpenproletariat, who he defined as the outcasts of society such as beggars, tricksters, entertainers, buskers, criminals and prostitutes. The political relevance of farmers has divided the left. In Das Kapital, Marx scarcely mentioned the subject. Mikhail Bakunin thought the lumpenproletariat was a revolutionary class, while Mao Zedong believed that it would be rural peasants, not urban workers, who would bring about the proletarian revolution.

Left-libertarians, anarchists and libertarian socialists believe in a decentralized economy run by trade unions, workers' councils, cooperatives, municipalities and communes, opposing both state and private control of the economy, preferring social ownership and local control in which a nation of decentralized regions is united in a confederation. The global justice movement, also known as the anti-globalisation movement and the alter-globalisation movement, protests against corporate economic globalisation due to its negative consequences for the poor, workers, the environment, and small businesses.

Leftists generally believe in innovation in various technological and philosophical fields and disciplines to help causes they support.

Environment

See also: Eco-socialism, Green anarchism, and Green politics

One of the foremost left-wing advocates was Thomas Paine, one of the first individuals since left and right became political terms to describe the collective human ownership of the world which he speaks of in Agrarian Justice. As such, most of left-wing thought and literature regarding environmentalism stems from this duty of ownership and the aforementioned form of cooperative ownership means that humanity must take care of the Earth. This principle is reflected in much of the historical left-wing thought and literature that came afterwards, although there were disagreements about what this entailed. Both Karl Marx and the early socialist philosopher and scholar William Morris arguably had a concern for environmental matters. According to Marx, "[e]ven an entire society, a nation, or all simultaneously existing societies taken together, are not the owners of the earth. They are simply its possessors, its beneficiaries, and have to bequeath it in an improved state to succeeding generations". Following the Russian Revolution, environmental scientists such as revolutionary Alexander Bogdanov and the Proletkult organisation made efforts to incorporate environmentalism into Bolshevism and "integrate production with natural laws and limits" in the first decade of Soviet rule, before Joseph Stalin attacked ecologists and the science of ecology, purged environmentalists and promoted the pseudoscience of Trofim Lysenko during his rule up until his death in 1953. Similarly, Mao Zedong rejected environmentalism and believed that based on the laws of historical materialism, all of nature must be put into the service of revolution.

From the 1970s onwards, environmentalism became an increasing concern of the left, with social movements and several unions campaigning on environmental issues and causes. In Australia, the left-wing Builders Labourers Federation, led by the communist Jack Mundy, united with environmentalists to place green bans on environmentally destructive development projects. Several segments of the socialist and Marxist left consciously merged environmentalism and anti-capitalism into an eco-socialist ideology. Barry Commoner articulated a left-wing response to The Limits to Growth model that predicted catastrophic resource depletion and spurred environmentalism, postulating that capitalist technologies were the key cause responsible for environmental degradation, as opposed to human population pressures. Environmental degradation can be seen as a class or equity issue, as environmental destruction disproportionately affects poorer communities and countries.

Global warming was the cover story of this 2007 issue of the Ms. magazine.

Several left-wing or socialist groupings have an overt environmental concern and several green parties contain a strong socialist presence. The Green Party of England and Wales features an eco-socialist group, the Green Left, which was founded in June 2005. Its members held several influential positions within the party, including both the former Principal Speakers Siân Berry and Derek Wall, himself an eco-socialist and Marxist academic. In Europe, several green left political parties such as the European United Left–Nordic Green Left combine traditional social-democratic values such as a desire for greater economic equality and workers rights with demands for environmental protection. Democratic socialist Bolivian president Evo Morales has traced environmental degradation to capitalist consumerism, stating that "[t]he Earth does not have enough for the North to live better and better, but it does have enough for all of us to live well". James Hansen, Noam Chomsky, Raj Patel, Naomi Klein, The Yes Men and Dennis Kucinich hold similar views.

In climate change mitigation, the Left is also divided over how to effectively and equitably reduce carbon emissions as the center-left often advocates a reliance on market measures such as emissions trading and a carbon tax while those further to the left support direct government regulation and intervention in the form of a Green New Deal, either alongside or instead of market mechanisms.

Nationalism, anti-imperialism and anti-nationalism

See also: Anarchism and nationalism, Anti-imperialism, Internationalism (politics), Left-wing nationalism, Proletarian internationalism, and Anti-Stalinist left

The question of nationality, imperialism and nationalism has been a central feature of political debates on the Left. During the French Revolution, nationalism was a key policy of the Republican Left. The Republican Left advocated for civic nationalism and argued that the nation is a "daily plebiscite" formed by the subjective "will to live together". Related to revanchism, the belligerent will to take revenge against Germany and retake control of Alsace-Lorraine, nationalism was sometimes opposed to imperialism. In the 1880s, there was a debate between leftists such as the Radical Georges Clemenceau, the Socialist Jean Jaurès and the nationalist Maurice Barrès, who argued that colonialism diverted France from liberating the "blue line of the Vosges", in reference to Alsace-Lorraine; and the "colonial lobby" such as Jules Ferry of the Moderate Republicans, Léon Gambetta of the Republicans and Eugène Etienne, the president of the Parliamentary Colonial Group. After the antisemitic Dreyfus Affair in which officer Alfred Dreyfus was falsely convicted of sedition and exiled to a penal colony in 1894 before being exonerated in 1906, nationalism in the form of Boulangism increasingly became associated with the far-right.

The Marxist social class theory of proletarian internationalism asserts that members of the working class should act in solidarity with working people in other countries in pursuit of a common class interest, rather than only focusing on their own countries. Proletarian internationalism is summed up in the slogan: "Workers of the world, unite!", the last line of The Communist Manifesto. Union members had learned that more members meant more bargaining power. Taken to an international level, leftists argued that workers should act in solidarity with the international proletariat in order to further increase the power of the working class. Proletarian internationalism saw itself as a deterrent against war and international conflicts, because people with a common interest are less likely to take up arms against one another, instead focusing on fighting the bourgeoisie as the ruling class. According to Marxist theory, the antonym of proletarian internationalism is bourgeois nationalism. Some Marxists, together with others on the left, view nationalism, racism (including antisemitism) and religion as divide and conquer tactics used by the ruling classes to prevent the working class from uniting against them in solidarity with one another. Left-wing movements have often taken up anti-imperialist positions. Anarchism has developed a critique of nationalism that focuses on nationalism's role in justifying and consolidating state power and domination. Through its unifying goal, nationalism strives for centralisation (both in specific territories and in a ruling elite of individuals) while it prepares a population for capitalist exploitation. Within anarchism, this subject has been extensively discussed by Rudolf Rocker in his book titled Nationalism and Culture and by the works of Fredy Perlman such as Against His-Story, Against Leviathan and The Continuing Appeal of Nationalism.

The failure of revolutions in Germany and Hungary in the 1918–1920 years ended Bolshevik hopes for an imminent world revolution and led to the promotion of the doctrine of socialism in one country by Joseph Stalin. In the first edition of his book titled Osnovy Leninizma (Foundations of Leninism, 1924), Stalin argued that revolution in one country is insufficient. By the end of that year in the second edition of the book, he argued that the "proletariat can and must build the socialist society in one country". In April 1925, Nikolai Bukharin elaborated on the issue in his brochure titled Can We Build Socialism in One Country in the Absence of the Victory of the West-European Proletariat?, whose position was adopted as state policy after Stalin's January 1926 article titled On the Issues of Leninism (К вопросам ленинизма) was published. This idea was opposed by Leon Trotsky and his supporters, who declared the need for an international "permanent revolution" and condemned Stalin for betraying the goals and ideals of the socialist revolution. Various Fourth Internationalist groups around the world who describe themselves as Trotskyist see themselves as standing in this tradition while Maoist China formally supported the theory of socialism in one country.

European social democrats strongly support Europeanism and supranational integration within the European Union, although there is a minority of nationalists and Eurosceptics on the left. Several scholars have linked this form of left-wing nationalism to the pressure generated by economic integration with other countries, often encouraged by neoliberal free trade agreements. This view is sometimes used to justify hostility towards supranational organizations. Left-wing nationalism can also refer to any form of nationalism which emphasizes a leftist working-class populist agenda that seeks to overcome exploitation or oppression by other nations. Many Third World anti-colonialist movements have adopted leftist and socialist ideas. Third-Worldism is a tendency within leftist thought that regards the division between First World and Second World developed countries and Third World developing countries as being of high political importance. This tendency supports decolonization and national liberation movements against imperialism by capitalists. Third-Worldism is closely connected with African socialism, Latin American socialism, Maoism, pan-Africanism and pan-Arabism. Several left-wing groups in the developing world such as the Zapatista Army of National Liberation in Mexico, the Abahlali baseMjondolo in South Africa and the Naxalites in India have argued that the First World and the Second World Left takes a racist and paternalistic attitude towards liberation movements in the Third World.

Religion

See also: Anarchism and religion, Buddhist socialism, Christian anarchism, Christian communism, Christian left, Christian socialism, Jewish left, and Islamic socialism

The original French Left was firmly anti-clerical, strongly opposing the influence of the Roman Catholic Church and supporting atheism and the separation of church and state, ushering in a policy known as laïcité. Karl Marx asserted that "religion is the sigh of the oppressed creature, the heart of a heartless world, and the soul of soulless conditions. It is the opium of the people". In Soviet Russia, the Bolsheviks under Vladimir Lenin originally embraced an ideological principle which professed that all religion would eventually atrophy and resolved to eradicate organized Christianity and other religious institutions. In 1918, 10 Russian Orthodox hierarchs were summarily executed by a firing squad, and children were deprived of any religious education outside of the home.

Today in the Western world, those on the Left generally support secularization and the separation of church and state. However, religious beliefs have also been associated with many left-wing movements such as the progressive movement, the Social Gospel movement, the civil rights movement, the anti-war movement, the anti-capital punishment movement and Liberation Theology. Early utopian socialist thinkers such as Robert Owen, Charles Fourier and the Comte de Saint-Simon based their theories of socialism upon Christian principles. Other common leftist concerns such as pacifism, social justice, racial equality, human rights and the rejection of capitalism and excessive wealth can be found in the Bible.

In the late 19th century, the Protestant Social Gospel movement arose in the United States which integrated progressive and socialist thought with Christianity through faith-based social activism. Other left-wing religious movements include Buddhist socialism, Jewish socialism and Islamic socialism. There have been alliances between the left and anti-war Muslims, such as the Respect Party and the Stop the War Coalition in Britain. In France, the left has been divided over moves to ban the hijab from schools, with some leftists supporting a ban based on the separation of church and state in accordance with the principle of laïcité and other leftists opposing the prohibition based on personal and religious freedom.

Social progressivism and counterculture

See also: Counterculture, New Left, Socialism and LGBT rights, and Socialist feminism

Social progressivism is another common feature of modern leftism, particularly in the United States, where social progressives played an important role in the abolition of slavery, the enshrinement of women's suffrage in the United States Constitution, and the protection of civil rights, LGBTQ rights, women's rights and multiculturalism. Progressives have both advocated for alcohol prohibition legislation and worked towards its repeal in the mid to late 1920s and early 1930s. Current positions associated with social progressivism in the Western world include strong opposition to the death penalty, torture, mass surveillance, and the war on drugs, and support for abortion rights, cognitive liberty, LGBTQ rights including legal recognition of same-sex marriage, same-sex adoption of children, the right to change one's legal gender, distribution of contraceptives, and public funding of embryonic stem-cell research. The desire for an expansion of social and civil liberties often overlaps that of the libertarian movement. Public education was a subject of great interest to groundbreaking social progressives such as Lester Frank Ward and John Dewey, who believed that a democratic society and system of government was practically impossible without a universal and comprehensive nationwide system of education.

Various counterculture and anti-war movements in the 1960s and 1970s were associated with the New Left. Unlike the earlier leftist focus on labour union activism and a proletarian revolution, the New Left instead adopted a broader definition of political activism commonly called social activism. The New Left in the United States is associated with the hippie movement, mass protest movements on school campuses and a broadening of focus from protesting class-based oppression to include issues such as gender, race and sexual orientation. The British New Left was an intellectually driven movement which attempted to correct the perceived errors of the Old Left. The New Left opposed prevailing authoritarian structures in society which it designated as "The Establishment" and became known as the "Anti-Establishment". The New Left did not seek to recruit industrial workers en masse, but instead concentrated on a social activist approach to organization, convinced that they could be the source for a better kind of social revolution. This view has been criticized by several Marxists, especially Trotskyists, who characterized this approach as "substitutionism" which they described as a misguided and non-Marxist belief that other groups in society could "substitute" for and "replace" the revolutionary agency of the working class.

Many early feminists and advocates of women's rights were considered a part of the Left by their contemporaries. Feminist pioneer Mary Wollstonecraft was influenced by Thomas Paine. Many notable leftists have been strong supporters of gender equality such as Marxist philosophers and activists Rosa Luxemburg, Clara Zetkin and Alexandra Kollontai, anarchist philosophers and activists such as Virginia Bolten, Emma Goldman and Lucía Sánchez Saornil and democratic socialist philosophers and activists such as Helen Keller and Annie Besant. However, Marxists such as Rosa Luxemburg, Clara Zetkin, and Alexandra Kollontai, who are supporters of radical social equality for women and have rejected and opposed liberal feminism because they considered it to be a capitalist bourgeois ideology. Marxists were responsible for organizing the first International Working Women's Day events.

The women's liberation movement is closely connected to the New Left and other new social movements which openly challenged the orthodoxies of the Old Left. Socialist feminism as exemplified by the Freedom Socialist Party and Radical Women and Marxist feminism, spearheaded by Selma James, saw themselves as a part of the Left that challenges male-dominated and sexist structures within the Left. The connection between left-wing ideologies and the struggle for LGBTQ rights also has an important history. Prominent socialists who were involved in early struggles for LGBTQ rights include Edward Carpenter, Oscar Wilde, Harry Hay, Bayard Rustin and Daniel Guérin, among others. The New Left is also strongly supportive of LGBTQ rights and liberation, having been instrumental in the founding of the LGBTQ rights movement in the aftermath of the Stonewall Riots of 1969. Contemporary leftist activists and socialist countries such as Cuba are actively supportive of LGBTQ+ people and are involved in the struggle for LGBTQ+ rights and equality.

History

See also: American Left, French Left, Left–right political spectrum, and History of political thought

The 5 May 1789 opening of the Estates General of 1789 in Versailles

In politics, the term Left derives from the French Revolution as the political groups opposed to the royal veto privilege (Montagnard and Jacobin deputies from the Third Estate) generally sat to the left of the presiding member's chair in parliament while the ones in favour of the royal veto privilege sat on its right. That habit began in the original French National Assembly. Throughout the 19th century, the main line dividing Left and Right was between supporters of the French republic and those of the monarchy's privileges. The June Days uprising during the Second Republic was an attempt by the Left to re-assert itself after the 1848 Revolution, but only a small portion of the population supported this.

In the mid-19th century, nationalism, socialism, democracy and anti-clericalism became key features of the French Left. After Napoleon III's 1851 coup and the subsequent establishment of the Second Empire, Marxism began to rival radical republicanism and utopian socialism as a force within left-wing politics. The influential Communist Manifesto by Karl Marx and Friedrich Engels, published amidst the wave of revolutions of 1848 across Europe, asserted that all of human history is defined by class struggle. They predicted that a proletarian revolution would eventually overthrow bourgeois capitalism and create a stateless, moneyless and classless communist society. It was in this period that the word wing was appended to both Left and Right.

The International Workingmen's Association (1864–1876), sometimes called the First International, brought together delegates from many different countries, with many different views about how to reach a classless and stateless society. Following a split between supporters of Marx and Mikhail Bakunin, anarchists formed the Saint-Imier International and later the International Workers' Association (IWA–AIT). The Second International (1888–1916) became divided over the issue of World War I. Those who opposed the war, among them Vladimir Lenin and Rosa Luxemburg, saw themselves as further to the left.

In the United States, leftists such as social liberals, progressives and trade unionists were influenced by the works of Thomas Paine, who introduced the concept of asset-based egalitarianism which theorises that social equality is possible by a redistribution of resources. After the Reconstruction era in the aftermath of the American Civil War, the phrase "the Left" was used to describe those who supported trade unions, the civil rights movement and the anti-war movement. More recently, left-wing and right-wing have often been used as synonyms for the Democratic and Republican parties, or as synonyms for liberalism and conservatism, respectively.

During the 20th century, war resulted in a dramatic intensification of the pace of social changes, and was a crucial catalyst for the growth of left-wing politics. Since the Right was populist, both in the Western and the Eastern Bloc, anything viewed as avant-garde art was called leftist across Europe, thus the identification of Picasso's Guernica as "leftist" in Europe and the condemnation of the Russian composer Shostakovich's opera (The Lady Macbeth of Mtsensk District) in Pravda as follows: "Here we have 'leftist' confusion instead of natural, human music".

Types

The spectrum of left-wing politics ranges from centre-left to far-left or ultra-left. The term centre-left describes a position within the political mainstream that accepts capitalism and a market economy. The terms far-left and ultra-left are used for positions that are more radical, more strongly rejecting capitalism and mainstream representative democracy, instead advocating for a socialist society based on economic democracy and direct democracy, representing economic, political and social democracy. The centre-left includes social democrats, social liberals, progressives and greens. Centre-left supporters accept market allocation of resources in a mixed economy with an empowered public sector and a thriving private sector. Centre-left policies tend to favour limited state intervention in matters pertaining to the public interest.

In several countries, the terms far-left and radical left have been associated with many varieties of anarchism, autonomism and communism. They have been used to describe groups that advocate anti-capitalism and eco-terrorism. In France, a distinction is made between the centre-left and the left represented by the Socialist Party and the French Communist Party and the far-left as represented by anarcho-communists, Maoists and Trotskyists. The United States Department of Homeland Security defines "left-wing extremism" as groups that "seek to bring about change through violent revolution, rather than through established political processes". Similar to far-right politics, extremist far-left politics have motivated political violence, radicalization, genocide, terrorism, sabotage and damage to property, the formation of militant organizations, political repression, conspiracism, xenophobia, and nationalism.

In China, the term Chinese New Left denotes those who oppose the economic reforms enacted by Deng Xiaoping in the 1980s and 1990s, favour instead the restoration of Maoist policies and the immediate transition to a socialist economy. In the Western world, the term New Left is used for social and cultural politics.

In the United Kingdom during the 1980s, the term hard left was applied to supporters of Tony Benn such as the Campaign Group and those involved in the London Labour Briefing newspaper as well as Trotskyist groups such as Militant and the Alliance for Workers' Liberty. In the same period, the term soft left was applied to supporters of the British Labour Party who were perceived to be more moderate and closer to the centre, accepting Keynesianism. Under the leadership of Tony Blair and Gordon Brown, the Labour Party adopted the Third Way and rebranded itself as New Labour in order to promote the notion that it was less left-wing than it had been in the past to accommodate the neoliberal trend arising since the 1970s with the displacement of Keynesianism and post-war social democracy. One of the first actions of Ed Miliband, the Labour Party leader who succeeded Blair and Brown, was the rejection of the New Labour label and a promise to abandon the Third Way and turn back to the left. However, Labour's voting record in the House of Commons from 2010 to 2015 indicated that the Labour Party under Miliband had maintained the same distance from the left as it did under Blair. ^,In contrast, the election of Jeremy Corbyn as the Labour Party leader was viewed by scholars and political commentators as Labour turning back toward its more classical socialist roots, rejecting neoliberalism and the Third Way whilst supporting a democratic socialist society and an end to austerity measures.