One of the key sources of false information that was fed to the US government about Iraq’s non-existent weapons of mass destruction program was from an Iraqi defector codenamed ‘Curveball’. He now proudly admits that he made it all up.
Of course, the reason he was believed uncritically was because he told the Bush-Cheney administration and its neoconservative warmongers exactly what they wanted to hear, and the government embellished his stories even further to sell that war to the public.