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

Credibility gap is a term that came into wide use with journalism, political and public discourse in the United States during the 1960s and 1970s. At the time, it was most frequently used to describe public skepticism about the Lyndon B. Johnson administration's statements and policies on the Vietnam War. It was used in journalism as a euphemism for recognized lies told to the public by politicians. Today, it is used more generally to describe almost any "gap" between an actual situation and what politicians and government agencies say about it.

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