Yep the US has been on a downward spiral for a long time now. The shine off the US has is now long long. I can remember when the US was respected for its promotion of human rights and freedom, well in many western countries anyways. Now the US tortures, locks people up with trial, covers up the murder of innocents and has no regard for international concerns. America has lost its was big time.
The US is now at a cross roads, it will be interested to see which way it goes I reckon. The age of having the biggest guns to shore up your security is over. Clearly the most important factor in a countries security will be economic this century and beyond. The US is an old tiger that has not learnt any new tricks, old infrastructure, an out of date political system, massive economic problems, huge social problems, out of control crime...the list goes onand on. If anybody thinks the US is a modern country then you are incorrect.
Saying that though I dont believe the US is in such a bad shape as what some commentators make out. They have the best schools in the world, a very hard working ethic, a mountain of assets and a willing population of motivated intelligent people.
The US is going to learn this century it will need to radically cut back on its military and try to find its place in this new world. It will be a humbling experience for the US, its just a matter of how much the US will kick and scream as it goes down a peg or two.