If you weren't watching the news closely the last few weeks, you may have missed the emerging tension between Japan and China. This is serious stuff, as noted by Peter Brookes in the column linked here. The important thing to remember that the Chinese do not tolerate protest. The anti-Japanese demonstrations are government sponsored, as alluded to in this cartoon by Cox & Forkum. Do not be fooled into thinking that this is actually a popular uprising of righteous anger at Japan, which is how I've seen it reported as. It is nothing more than Chi-Com propaganda, and as such should always invite a deeper look. Brookes' piece does this, and Cox & Forkum's cartoon is also on point regarding the protests.
My analysis is this: Japan may have to go nuclear to deter China and it's puppet, North Korea. We should support them if they choose this course. Democratization is the only solution to China's belligerent behavior, and it can't be imposed from outside the country. Until then, military deterrence on the order of what we did vs. the USSR is needed. Japan is in the position Europe was in during the '80's, on the front line of the new cold war. Fortunately, Japan realizes that it will have to "do for itself" regarding China with the US occupied with the war on terror, and seems more ready to assume defense responsibility than the Europeans turned out to be.
Japan is a well-respected democracy, and China is among the most repressive dictatorships on the planet. People who worry about the economic devastation of cutting trade with China may have to start thinking about the real devastation that China (and No. Korea's) nuclear arsenal may cause. They already do in Japan.