Like GW Bush, it will probably be whichever president is the next to preside over a deadly attack on American soil.
I would not be surprised if the country is dragged into another war during the current administration. Could be Georgia (the country), Pakistan, Israel, Somalia, Iran, Sudan, or any number of other destabilized nations in the region.
Bin Laden attacked the twin towers in the early 90s. It was originally a big bomb in the basement / garage floors, but the bomb wasn't strong enough to topple the towers.
We didn't start the fire. It was always burning, since the world's been turning
EDIT: if you're going to downvote, at least engage.
Considering that the "defense" budget has increased, I doubt the empire is ending anytime soon. More wars. You have to justify your budget. My guess is that we will be "defending" ourselves all over asia, africa, south america, etc. Now that iraq, syria, libya, afganistan, etc were turned to rubble ( mission accomplished ), we'll need to spread "democracy" all over the world.
We're like the borg. We have to assimilate them all. It's amazing how long we've been able to get away with being so evil and cruel.