Yeah for about 10 years...
And people may have hated the US for longer but that doesn't mean that the US not keeping their promises in Afghanistan wasn't a damn good reason for them to do shit like that. Now saying the US thought it would hit two birds with one stone, pretty much makes what they did okay? If anything it makes Osama's action even more logical. How would the US deal with betrayel like that? By going to war right? Hell they have for lesser things.
Now Osama isn't the only terrorist i know, but all of them whether we like it or not have reasons for what they are doing. Often reasons that we would support if we were in a similiar situation. Maybe we wouldn't agree with the method in which it was done. But Afghanistan could hardly declare a war on the US.
And now that the US has invaded Iraq more and more terrorist are going to come with a in their eyes damn good reason to attack the US. War is not the answer against things like that, it may work against country's but you can't rage war on an ideal. If anything you just strengthen the ideal.