North Korea conducts second nuclear test

Shortly after the U.S. Geological Survey reported a "seismic event" in the region, the North Korean government confirmed that it had conducted its second nuclear test "as part of the measures to bolster up its nuclear deterrent for self-defense in every way."  Ploughshares Fund grantee Jim Walsh of MIT's Security Studies Program told CNN that "nothing good" can come from Monday's test,  "but it doesn't mean they're going to have a real working nuclear weapon tomorrow or next year." He said that North Korea remains "years and years" away from having a weapon it could put atop a long-range missile.