Kyodo/Reuters
The United States, Japan, and South Korea vowed Wednesday to present a united response to North Korea’s claim to have successfully detonated a hydrogen bomb. The White House said President Obama spoke with both South Korean President Park Geun-Hye and Japanese Prime Minister Shinzo Abe. Statements from all three countries said the powers have “agreed to work together to forge a united and strong international response to North Korea’s latest reckless behavior.” The Hermit Kingdom said it conducted a “miniaturized” hydrogen bomb test Wednesday, but experts have argued the seismic activity generated by the blast was not big enough to qualify as a full thermonuclear explosion. South Korea said Thursday it would retaliate by resuming cross-border propaganda broadcasts, which the North has considered an act of war.