Just like America itself England can be blamed. Since there are already a bunch of WW2 answers, I’ll go back to post WW1 where England and France decided to carve up the middle east in their own interests. This created a bunch of countries with boarders that made little sense, mainly so one big influencal leader could give countries to his family members. Then jump ahead to an Australian showing up in Iran agreeing to look for oil and if he finds any he keeps 90% of the profits for 60 years. Once he found oil and made a bunch of money England said that is too good of a deal and just took over the company and changing its name to BP. Iran said this deal sucks and demanded a better deal, England said fuck you and went and asked America to step in and help them keep their deal. America sent the CIA in to cause problems, and the CIA was successful. The new leader still forced England to accept a more fair deal, but pissed off the people of Iran. So when the dictator was overthrown the new leadership was founded on a very popular policy of death to America because the CIA did what England asked them to do.