I don't like to get into politics here, but...
The U.S. want's to be able to nuke countries that haven't done nothing wrong! Yes, that is nuke. And by 'having done nothing wrong', I mean 'have been accused by the CIA of intending to use WMDs'. Such as Iraq, I suppose. Had this doctrine been in place a few years ago we would most likely have had another couple of nuked cities in the world.
Think about it.
Don't you feel much safer now?