The USA Patriot Act was not drafted after 9/11. It was drafted before. 9/11 was an excuse by the US Government to capture civil liberties, wiretap phones, expand the military/surveillance state, and deny the vast majority of Americans their rights to free expression, association, and of course, freedom of religion (if you happen to be Muslim). 

It has always been illegal to be a terrorist. Existing laws would have been perfectly fine in going after the perpetrators of 9/11. 

But no politician has ever said that we should curtail the power of the surveillance state, have they?