[DoItToMe81]

I find it very odd that Americans seem to not be able to understand how a highly nationalist people may object to them staying past their welcome date and seek to attack them on their own accord, and that most of these groups existed well before acquiring Iranian funding.

Most Iraqis still remember tragedies like the Mahmudiyah massacre. The government of the time took them into account and promised to have American bases closed, but reneged. I think you can see how events like that being rampant might drive people to fight, even a generation later.