[Zhang Fei]

Because the cat is out of the bag - the US umbrella was not enough to keep NK from testing a nuclear device, a device which Japan is not supposed to have or desire. I think if the nut in Pyongyang has a bomb, Japan will want some insurance in case a weak Carter/Kerry/Clinton type president wins in 2008.

If Japan splits off from the nuclear and conventional umbrella provided by Uncle Sam, China will have achieved its objective in getting Kim to up the ante - to confront Japan alone, instead of Japan and Uncle Sam. China also gets to cut Japan off from supporting the US over a Taiwan flare-up. The abrogation of the US-Japan mutual defense pact would also mean the withdrawal of US troops from Japan, which would increase the American response time if China invades Taiwan.

I really can't see how a nuclear Japan that is no longer formally allied with the US is bad for China. Does anyone think Japan would use nukes over the disputed Senkaku Islands? The fact is that a nuclear Japan is a Japan that faces China alone - without an American tripwire force to oblige a US president to come to Japan's rescue either in territorial disputes or disputes over sea lanes.

[chilepepper]

If Japan splits off from the nuclear and conventional umbrella provided by Uncle Sam

That isn't what will happen. Japan will have a few of its own nukes *as well* as the existent nuclear umbrella, exactly like the UK, and to some extent the French force de frappe

With its own nukes, Japan can strike back on its own if attacked without having a weak US president mulling over an NK nuclear threat against L.A. in deciding whether or not to strike back at a nuclear attack on Sapporo, for example.

The big nuclear umbrella will protect against the big boys like China and Russia if it ever comes to that...

[gogeo]

If Japan splits off from the nuclear and conventional umbrella provided by Uncle Sam, China will have achieved its objective in getting Kim to up the ante - to confront Japan alone, instead of Japan and Uncle Sam. China also gets to cut Japan off from supporting the US over a Taiwan flare-up. The abrogation of the US-Japan mutual defense pact would also mean the withdrawal of US troops from Japan, which would increase the American response time if China invades Taiwan.

This would happen if one assumes that having a nuclear Japan would not be to our advantage, that we would not agree.

Obviously, it is, and we would.