After North Korea's nuclear bomb test, the People's Republic of China insists that "punishment should not be the purpose" of any response. Maybe the problem isn't North Korea, but China. There's another, more ominous reason for China's reluctance to help: The country is responsible for much of the proliferation of nuclear technology to terrorist states in recent years. That includes its main client, North Korea. As the State Department noted in a 2003 report, "Chinese state-owned corporations have engaged in transfer activities with Pakistan, Iran, North Korea and Libya that are clearly contrary to China's commitments to the U.S." China...