The best lie that America ever told the world (best exemplified by the 1939 World’s Fair[1]) was that democracy and capitalism go hand in hand. But when the U.S. blinked after the 1989 Tienanmen Square massacre and kept on buying cheap goods from China, it became clear that the Western world - the only long term bastion of democracy - cared more about capitalism than democracy, and China showed the world that you don’t need democracy for capitalism. Democracy has been in decline ever since, along with human rights.
[1] https://en.m.wikipedia.org/wiki/1939_New_York_World's_Fair