We are not perfect, as no one is. We do/have done the best thing for the situations we encounter and we continue to strive to do. What you fail (horribly) to realize is that our politicians are not psychic. We have a long tradition of vanquishing our enemies (humanely as possible in most situations), helping them rebuild, world-wide humanitarian efforts, and are the best thing that has happened to the world when it comes to human rights and ethics. We cannot gauge who will rise up from the ashes of our conquests over true worldwide evil. If we worried about that, your country would still be in shambles or you'd be a pawn of Hitler still (see link at bottom)! Also, If we let our enemies continue to live and breathe freely, then they will only try to take us over (us being the world). What you fail (again horribly) to see is that non-action is worst and is the quickest way to be defeated. Ever heard of "a good offense is the best defense"?
You are basing your opinions on some utopian society that does not exist but is most closely mirrored by (not your country or any other, but) the USofA. Until you can come up with a better society of your own, I think you should thank us for your freedom, and ease up on the criticizing. (Austria was taken by Germany twice and freed by us and their economy is greatly helped by the US even today and our military is there to protect your country since the vast bulk of UN forces are American.)
http://www.austria.org/oldsite/jul97/stephen.htm Bottom line, quit comparing the US to a utopian society. Any nation except for the Kingdom God sets up when Jesus returns will fall short. The US has done tremendous amounts of good and small amounts of bad and the bad was either by mistake or was a byproduct of a greater accomplishment. No one except for God is perfect, period.