There are many differences, chief of which, IMO, is that the occupation of Japan was not fiercely resisted in that part of the world within a context of religious fervor and competing world views.
Not only is the occupation of Iraq being violently resisted by the Iraqis, it is seen as an assault on the entire region by most of its inhabitants. And most of the world views the invasion and occupation as a violation of international law. Contrast current opinion of the U.S. with that of the 1945 power that saved the world from facism.
I don't agree with everything Reese wrote in this article, and you have a point that there are exceptions to every rule. Japan would be the exception about imposing democracy at gunpoint. Iraq will not be.
The main principle of the article stands... a government cannot last unless the charter of that government is widely supported by the people.
Cheney/Rumsfeld may or may not have been able to transplant democracy to Iraq
IF they had relied upon counsel from the true experts on the region and had devised a well-thought plan to implement immediately after Saddam was deposed.
But the neocon ideology does not allow for any facts or advice that challenges their preconceived beliefs and agenda. By their own arrogance and hubris they have destroyed any chance to implement their current justifation for the war -- democracy.
I think we all know that
true democracy in Iraq and the Middle East would not be kind to American (and especially neocon) interests. We have a history of propping up repressive governments in that region. The notion that the current crop of imperialist hawks and corporate hegemons are crusaders for democracy is a notion they have been very successful in getting the American people to believe, but the "beneficiaries" of their crusade are not buying it.
This same cabal is doing real damage to American democracy.
For more on the occupation of Japan:
http://www.bayarea.com/mld/mercurynews/news/columnists/daniel_sneider/6322046.htm(edited for spelling)