When Mossadegh was in office, Iran was more or less owned by the US and England, then the premier decided to change the course of his government towards a more independent policy. His first step was to nationalize the largest Iranian oil company which prompted the CIA to devise a plan to get rid of him (
Operation Ajax, a joint CIA/MI6 project with a lil' help from the Pahlavi clan). All these events from the 50s to to the 70s were the precursor to the Iranian revolution which took place in the late 70s, so consequently, the US ordered their puppet Saddam Hussein to invade Iran and get rid of the Muslim republic that had just been founded - which didn't work out, Saddam eventually turned against America and the rest is history. Oh, and Israel helped Saddam by bombing alleged production sites of highly enriched Uranium while in reality, they wanted to deliver a death blow to the Iranian infrastructure. A few years later, they were shit-scared of Saddam's Scud missiles and cried to daddy Bush and later on Clinton to save their asses...
It's all a huge mindfuck, man...