What the hell did we do to make those people hate us so much? (pre-iraq war)
Who? Iraq? Well, you killed about 20,000 of them during the Gulf War, then put the under sanctions which cost between 500,000 and 1,000,000 civilian lives.
Iran? You installed an unelected despot who went on to rule for twenty years so you could have easy access to oil.
Lebanon? You invaded, along with French forces, in the 80s.
Oh, and Israel/Palestine. Though that's a more controversial point, it's also the most widely cited cause of anti-Americanism. I guess that in instances where there is no concrete grievance, that's what people fall back on.