Who said anything about "most"? We don't have "most" of our military in Japan.
Anyway if you really believe that "no one else need ever worry of US" then that's great. Does that mean people will stop complaining and whining about our belligerent unilateralism?
of course if US currency keep dropping, Iraq become very expensive...also with what I read of drain on Reserves/Guard of US military, let us see how long deployment of 120k last....not to mention if locals get tired of it.
Yes, everything is going just horribly.
You can keep telling yourself that, if it's that important for you to believe it.