Why you shouldn't panic about North Korea's H-bomb

The web is atwitter in response to North Korea's claim to have exploded a hydrogen bomb — essentially an atomic bomb on steroids — and the international community is wondering what to make of this latest development in Hermit Kingdom. Last month, the mercurial leader Kim Jong Un abruptly canceled the Beijing leg of the tour of his all-girl rock and roll band Moranbong; this month he's promising to up his Armageddon game. What should we make of this?

North Korean leader Kim Jong Un watches a firing contest of the KPA artillery units at an undisclosed location in a photo released by North Korea's Korean Central News Agency in Pyongyang on Jan. 5, 2016.
KCNA | Reuters
North Korean leader Kim Jong Un watches a firing contest of the KPA artillery units at an undisclosed location in a photo released by North Korea's Korean Central News Agency in Pyongyang on Jan. 5, 2016.

While it would be foolish to ignore North Korea's latest nuclear provocation, it is prudent to ask two questions before we panic: First, is there really evidence that North Korea has traded up from the atomic bomb (which produces a blast measured in the tens of thousands of tons of dynamite) to what was referred to in the early days of the nuclear age as the "Super" (hundreds of thousands of tons)? Second, if by chance it has, what would that development really mean for the United States and its regional allies?

I think that there remain grounds to believe that this claim, like so much previous rhetoric from North Korea, is more nuclear bluster than real strategic progress. And even if North Korea has managed to move from fission to fusion, that hardly changes the strategic equation on the Korean Peninsula or in the region.

On the former, we have a number of ways of gauging the status of North Korea's nuclear program. Overhead reconnaissance — pictures from satellites — can provide tell-tale evidence of an unground test by documenting tunneling and excavations at North Korean military facilities. Reports indicate that some sort of test was conducted this week.

But determining whether it was actually a hydrogen weapon is a different matter. Barring a human source in the North Korean military, the best indicator of the magnitude of the explosion is seismic data. According to the U.S. Geological Survey, the agency that monitors earthquakes but can also assess the size of nuclear tests, this event was actually smaller than a previous explosion in 2013 that is widely regarded as having been an atomic test. In other words, there are grounds for thinking that what we're seeing today is simply an increase in the magnitude of North Korea bluster rather than a real increase in its nuclear capability.

But let's assume the worst case: North Korea has joined the thermonuclear club. Does that really change anything? My sense is not much. To begin with, true nuclear superpower status entails not just being able to produce a bigger bang; it also requires having reliable delivery capability for that bang. North Korea has not had an impressive track record in recent missile tests and under the best (worst) case could field only a smaller number capable of carrying nuclear warheads and striking targets outside the Korean Peninsula.

In contrast, the United States could respond to any North Korean attack by delivering nearly 1,400 megatons of thermonuclear explosive on more than 5,000 warheads. Just to put our arsenal in perspective, this represents the equivalent of 1.4 billion tons of TNT that could be dropped on one country, which dwarfs the 3.4 million tons dropped by all of the allies during the entire course of World War II. While I am not minimizing the damage that one or a handful of thermonuclear warheads could do to the United States or its allies, North Korea faces the prospect of literal obliteration if it uses its rudimentary capability.

Like his father and grandfather before him, he is, above all else, committed to maintaining his grip on power in Pyongyang. That's not nice but it is certainly rational. Indeed, there is good reason to think that the primary purpose of his rudimentary atomic arsenal, and his escalating thermonuclear braggadocio, is ultimately about preserving his tenuous hold on power.

While North Korea's nuclear capability no doubt decreases the already nearly infinitesimal likelihood that the United States or South Korea will invade the country for the purpose of regime change, it does nothing to meet the real threat to Kim's hold on power: Internal discontent generated by the continuing economic failure of his regime. It will not happen tomorrow or even in 10 years, but Kim should be a lot more worried about his regime collapsing of its own weight than we should be about his thermonuclear swagger.

Commentary by Michael Desch, a professor of political science at Notre Dame and director of the Notre Dame International Security Center. He is co-author of the book "Privileged and Confidential: The Secret History of the President's Foreign Intelligence Advisory Board" with K. Michael Absher and Roman Popadiuk. Follow him on Twitter @mcdesch.

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