After two years of essentially fruitless negotiations with Pyongyang, it seems justifiable to conclude that the era of North Korea acquiring nuclear-armed missiles has ended and given way to the era of North Korea as a permanent, de facto nuclear weapons state. While negotiations will continue, it is appropriate to raise the question of how this situation came about.

As a case study in international politics, what North Korea achieved is remarkable. The ancient and influential Greek historian Thucydides is celebrated for the concise wisdom of his observation that ¡°the strong do what they will, and the weak suffer what they must,¡± a summary of the neorealist view of international politics.

In this case the power gap between the ¡°strong¡± United States and ¡°weak¡± North Korea was immense. The U.S. economy was roughly 100 times the size of North Korea¡¯s, and the U.S. also boasted the world¡¯s most capable conventional military forces plus a nuclear arsenal that could have incinerated every North Korean city. Yet this comparatively small country managed, despite the superpower¡¯s awareness and opposition, to acquire a capability that made itself exponentially more potentially dangerous to the superpower.