Analysis North Korea nuclear test claim unlikely to force fresh negotiations with U.S. and allies

rth Korea’s claim that it had successfully detonated a hydrogen bomb on Wednesday elicited an angry if familiar chorus of condemnation from countries including the United States, South Korea, Japan, China and various arms-control organizations. But Washington and the international community may yet again find it hard to muster the will to strengthen sanctions or take bold steps to lure North Korea back to the bargaining table any time soon, experts said.

The U.N. Security Council was preparing to meet Thursday to discuss Pyongyang’s assertion that it had exploded a “miniature” H-bomb. If confirmed, it would be the reclusive Communist state’s fourth nuclear test since 2006 but the first using fusion technology. North Korea’s nuclear tests in 2006, 2009 and 2013 are all believed to have used plutonium-based, or perhaps uranium-based, atomic weapons.

Hydrogen bombs, also called thermonuclear bombs, can potentially be much larger than atomic weapons, which rely on fission for their explosive power. However, initial data about Thursday’s blast in North Korea indicated it was not substantially larger than the country’s 2013 test, said Daryl Kimball, executive director of the Washington-based Arms Control Assn.