The escalating tension in East Asia brought on by North Korea’s nuclear brinkmanship has forced Pacific allies and opponents alike to rethink their circumstances and their options. Differences in approach have led the U.S. and South Korea to reconsider their security roles on the Peninsula. China, just starting to savor its membership in the community of free-market economies, seems at a loss on how to handle its ill-behaved protege. As Kim Jong-il cranks up his bad-boy behavior, people in both Tokyo and Washington are starting to think the unthinkable – that Japan itself could, and maybe should, go nuclear.