Analysts dubious over North Korea's H-bomb claims

North Korea’s said Wednesday that it had carried out a “successful” hydrogen bomb test, a claim that, if true, would represent a significant and dangerous step forward in its nuclear weapons programme, experts say.

Pyongyang has carried out nuclear tests before – in 2006, 2009 and 2013. But what would makeWednesday’s test significantly more worrying to the international community is the claim that it was a vastly more powerful hydrogen bomb that was detonated, rather than the fission bombs seen in previous tests.

“A fission bomb is where you split atoms into smaller atoms, and that’s very much like what the bombs dropped on Hiroshima and Nagasaki [during WWII] were like – so still big nuclear explosions,” nuclear policy and arms control expert Crispin Rovere told FRANCE 24.

“But an H-bomb is so much greater than that. You combine small elements, fuse them together, and that releases vast amounts of energy.”

North Korea also claimed that the weapon it tested was “miniaturised”, meaning small enough to attach to a missile. If true, this could that mean Pyongyang is close to meeting the ultimate goal of its nuclear weapons programme: to develop a long-range nuclear capability, able to strike targets thousands of miles away including the United States.

“In order to do that it’s not enough just to have a nuclear explosion. You need to have something that is small enough to fit on your missiles so you can effectively deliver that weapon,” said Rovere.

Doubts over claims

The possibility that the country has reached this important milestone in the development of its nuclear programme could have frightening ramifications, said David Galbreath, professor of international security at Bath University and an expert on arms control.

“The fear is that North Korea could have submarines armed with nuclear weapons operating off the coast of Washington state, for example, capable of striking the continental United States,” he told FRANCE 24.

North Korea has been known to exaggerate its military prowess, however, and significant doubt remains over whether the device tested on Wednesday was indeed a hydrogen bomb.

While the US Geological Survey detected a 5.1-magnitude seismic event in the vicinity of North Korea’s Punggye-ri nuclear test site, which suggests that a nuclear explosion did take place, the modest size of the explosion has raised doubts over Pyongyang’s claims.

“Initial indications are that the predicted yield of the explosion is very close to that of previous fission bomb tests conducted by North Korea,” Dr Matthew Cottee, research associate for non-proliferation and nuclear policy at the International Institute for Strategic Studies, told FRANCE 24.

“But without a lot more information it’s very difficult to say.”

Rovere agreed with that assessment, saying that the seismic activity on Wednesday suggests that “there was a nuclear explosion, but on a much smaller scale than we would expect from a typical successful hydrogen bomb test”.

North Korean H-bomb ‘only a matter of time’

But while Pyongyang may well be overstating the extent of its nuclear capabilities, an H-bomb-armed North Korea is far from an outlandish proposition, say some experts.

Policy analysts “seem pretty convinced that we are entering the age of the North Korean H-bomb”, said Galbreath. “Even if this was not a successful hydrogen bomb test it is something that is going to happen sooner or later, unless there is some kind of Iran-style nuclear agreement, which seems extremely unlikely.”

That North Korea may have carried out a successful H-bomb test “does not come as a surprise”, Cottee agreed.

“This is something we have been talking about for a while in relation to North Korea – an H-bomb test was only a question of when, not if.”

With Wednesday’s test came another blow to already moribund efforts to rein in North Korea’s nuclear programme, eliciting condemnation from the international community – including China, whose traditionally strong relations with North Korea seem to be rapidly deteriorating.

Several rounds of six-nation talks involving South Korea, the US, China, Japan and Russia on reaching an agreement with North Korea over its nuclear programme have largely failed, and while there have been many bilateral attempts to engage Pyongyang, "North Korea has now clearly rebuffed any attempt at diplomatic negotiations with this test,” said Cottee.

Pongyang, he said, is sending a message that it is “able to develop its nuclear weapon and missile programme pretty much unchecked by the international community”.