I am only responding to your posts, American bombing raids have killed Allied forces, but what they did in Salala was different, Look the point here is very simple America is super Power not just militarily but economically, no one can go against them and they can twist any arm them want to by using their military or Economic institutions and Allies. Right now they are leaving from Afghanistan, and most of the planes will be Transport which carries soldiers and equipment, it will be stupid of Pakistan to not give them a corridor for that, As Americans are leaving it is in Pakistan's favor that they leave with good terms with Pakistan.