James Traub cites Germany and Japan as the resounding post-war successes.

Question: What are the great success stories of nation building?

Jim Traub:    Well, obviously, the great story is the rebuilding of Germany and Japan after World War II.  Now, because those countries are such core members of the democratic world, it’s not easy to remember that neither one had a democratic past.  Germany had the very brief lived Weimar Republic.  Japan had no real experience with democracy at all.  So, it was a no sense predetermined that either one would become a democracy but that was the explicit goal of American policy.  It was a policy that was willing to spend money, be patient, seek deep changes, not just in the political structure, in many cases, in the economic structure as well, and actually faster than people thought within 5, 6, 7, 8 years.  Those countries were clearly functioning democracies the United States was able to [weave] faster than they thought.  So, those were examples where a really massive effort at state building took place, but it is also important to say they took place in countries which, although, they didn’t have a democratic tradition, they were middle class countries with the tradition of liberal institutions.  And so, it was also for all the difficulties, a lot easier than the kinds of things that the Bush Administration undertook in the Middle East or even the sorts of nation building activities we hope to engage in weak states in Africa, for example.