For decades, North Korea has been moving to acquire and develop deliverable nuclear weapons—the bigger, the better. Today’s hydrogen weapon test is a major step in that direction and a threat to the United States and its security commitments in Northeast Asia and beyond.
Nuclear weapons are not cheap. So why does a desperately poor country like North Korea want them so badly? Could it be, as some have argued, that the prestige-challenged Kim regime wants them just to enhance its image? Or perhaps the weapons are just for defensive purposes. Every year, the United States and South Korea hold joint military exercises that are designed to confront a(nother) North Korean invasion of the South. And every year, the North Koreans stage an apoplectic response, accusing the United States and South Korea of preparing to invade the North. Such explanations of North Korean behavior suggest it is defensive in the face of these threats, and that use of nuclear weapons is remote, almost theoretical, for “regime survival.” As long as no one invades them, there is nothing to worry about.
In fact, North Korea’s acquisition of a nuclear arsenal is far more focused, offensive, and dangerous. It is designed to pose a direct challenge to the U.S. security commitment to South Korea and Japan. In the event of hostilities (i.e., a North Korean attack on the South) or even just exercises, the threat of using nuclear weapons against the United States could put a U.S. president in a dilemma: Either fulfill alliance responsibilities, and in so doing expose the American public to a possible attack, or blink and in so doing undermine U.S. treaty commitments around the world.