1. By overthrowing a democratic government in the first place to make the Shah a dictator, creating the seeds of revolution; and

2. When it becamne clear that Iran was "lost" (to the West) and fearing a takeover by the Communists and Iran falling into the Soviet sphere of influence, the US got Saddam Hussein, our then-puppet in Iraq who we used to stoke a war for a decade killing more than a million people as an aside, to release the Ayatollah Khomenei from prison in the hopes that the Islamic fundamentalists rather than the communists would win the revolution.