I think China's military advancement will eventually force a nuclear deterrent (they're aggressively stealing US secrets and have built two Aegis destroyers) and the US will eventually approve of Japan acquiring a nuke if not sooner because of N.Korea.
You said -- "I think China's military advancement will eventually force a nuclear deterrent (they're aggressively stealing US secrets and have built two Aegis destroyers) and the US will eventually approve of Japan acquiring a nuke if not sooner because of N.Korea."
Well.., there goes nonproliferation right out the window...
http://en.wikipedia.org/wiki/Nuclear_Nonproliferation_Treaty
Regards,
Star Traveler