I'd ask, "did US foreign policy unintentionally provoke the 9/11 attacks?"
I think that'd narrow the debate to a more realistic level. 'Cause a lot of people try to attack the idea that we expressly attacked the Arab world and literally tried to directly provoke them, which just isn't the case. Some basically were religiously outraged at our presence in the Muslim world. A lot of people over there don't like it, but there are a few who are crazy enough to carry out terrorist attacks to make a statement about it.