RE: Japan's Secret Army
I don't know so much about China, but I know that what nuclear weapons the North Koreans possess they possess because of the US breaking promises. And as for Japanese aggression, they have already claimed various islands. And whilst they may have no real "military" installations of their own, they certainly allow plenty of them to be built and maintained. In short, I agree that China and North Korea are acting increasingly aggressively, but I really don't think they are the ones responsible. All current problems seem to pretty much undeniably trace back to US - and other western - interference in the region: even the main reason for Japan's imperialistic foray into mainland East Asia was in response to European and American empire-building. So it seems to me that the only requirement for talking about Chinese and North Korean aggression is to first ignore past and current Japanese and Japanese-sanctioned aggression.
No, they possess nuclear weapons as a bargaining chip to get more welfare. That and they cannot really afford to maintain the massive conventional forces they have, all those soldiers and artillery pieces cost a fortune to maintain, nuclear weapons are relatively cheap as a deterrent.
Seems like you want to blame Americans for problems that began well before we even showed up. The east is like the middle east, they have been fighting each other for thousands of years, westerners are late to the party, blaming them is foolish.
What little military capacity Japan currently has is dwarfed by both china and N. Korea, the N. Koreans have a million man standing army in addition to their nuclear arsenal.