The magnitude of the explosion, now revised to 5.1, is significantly larger than North Korea's previous nuclear tests in 2006 (4.3) and 2009 (4.7). Seismic scales are logarithmic, so 4.9 is much larger. The corresponding size of

North Korea's show of defiance, possibly timed to overshadow Obama's speech, has come at a time when many of the president's leading advisers on Asia have left the administration and have yet to be replaced. It will require a statement of presidential

The regime in North Korea must know there will only achieve security and prosperity by meeting See More. America will continue to lead the effort to prevent the spread of the world's most dangerous weapons. The regime in North Korea must know there

UNITED NATIONS — At the United Nations, the desire to impose ever harsher sanctions on North Korea to try to curb its development of nuclear arms and ballistic missiles has long stalled in the face of Chinese opposition — the standard chain of events

SEOUL, South Korea — North Korea's neighbors bolstered their military preparations and mobilized scientists Wednesday to determine whether Pyongyang's third nuclear test, conducted in defiance of U.N. warnings, was as