A comparision with the rebuilding of Japan and Germany is often made in regard to the conflict in Iraq. Why did that work so great and doesn't it seem to work now? First of all, it is still early. The Marshall plan only came into action 1948. The Nurnberg trials ended in 1949. Two month after the Second World War, nobody could believe it was really over. And the Americans are still in Germany.
But there is something else too. When the Alieds came to Germany and Japan, they came to conquer and punish. The Germans and Japansese had been bad. They lost the war and now everything was going to be different. That the alied forces took over the government was only logical. We'll take over and maybe, if you're nice, we'll let you be independent again. The collective guilt in the Axis made them accept the victors.
In Iraq the Americans have always said: we have nothing against the Iraqi people, it is Sadam Hussein we're after. The Iraqis are good, they are the victim of an evil regime. Then after the war, it is only logical that the Iraqi would say: if we're good and only Sadam was bad, can we please have our indepence right away, now that he's gone? There is no collective guilt.