North Korea dropped a bomb underground yesterday, conducting its third successful nuclear test since 2006 and creating a small seismic event. The explosion was about twice as large as the last test, in 2009, though the bomb is thought to have been made with plutonium, and not the much scarier uranium. U.S. officials had been expecting such a test, and the president has already issued a statement condemning it—as has China, North Korea's only regional ally—though it likely won't stop North Korea from conducting a fourth test in the coming days. North Korean officials remain unbowed, literally: "The DPRK will never bow to any resolutions," a top diplomat told the Conference on Disarmament.

[GIF: North Korean TV broadcast.]