Fifteen of the 9/11 hijackers were from Saudi Arabia, two from the United Arab Emirates, one from Egypt, and one from Lebanon. Who were you going to bomb again?

Regardless, an unknown number of Afghans and at least 100,000 Iraqi civilians (a very conservative estimate) have been killed since America invaded. I think "payback" for the 2997 civilians (not all of them Americans, either) that died in the World Trade Center has already been exacted many times over.