Why on earth did anyone think Obama deserved a peace prize?

This has to go down in history as the most bewildering decision ever made. How can you give a peace prize for someone who is taking US into war - Iraq, Pakistan, Afghanistan, Libya...who next? Probably the world has just re-defined peace in which case Bush and Dick Cheney should at least have got a nomination along with Hitler, Mussolini and Stalin as the wold peace makers.