North Korea's hydrogen bomb test and the questions it raises


North Korea announces that it has tested a hydrogen bomb. This raises three questions:  Is it true? Should we be worried about it? What can we do about it?

The answer to the first question is: it depends on what you mean by a hydrogen bomb.

The first atomic bombs created an explosion by the fission of uranium or plutonium atoms. In 1951, when the world was just coming to terms with the power of the bomb dropped on Hiroshima which dwarfed the power of any weapon then in existence, the United States exploded a bomb that was a thousand times as powerful as the Hiroshima bomb. This was the hydrogen bomb, or thermonuclear bomb. The hydrogen bomb generally works by using an atomic bomb as a trigger for a more powerful second stage fusion of atoms, a process that involves the use of tritium, an isotope of hydrogen, hence the term “hydrogen bomb.” Furthermore, unlike the Hiroshima bomb, there was no limit to its power.    

Russia, Britain and then France followed suit. Now the destructive power of the most powerful nuclear weapons was measured, not in kilotons, 1,000 tons of tnt equivalent, but megatons, a million tons equivalent.

In the 1960s, US bombers were flying with four 25-megaton bombs, an unimaginable amount of destructive power. This was terrifying, and “ban the bomb” movements attracted mass support all over the world. Later governments  realised that there was no point in building bombs of this power, and today most nuclear weapons are below a megaton.

Building a hydrogen bomb is much more difficult and technically demanding than building an “ordinary” atom bomb, and it is unlikely that North Korea has achieved this.

But this is where the definitions are important. Scientists have worked out how to work part of the fusion process into fission bombs to make them more effective. These are known in the trade as “doped” fission bombs. It is quite possible that North Korea has created one of these, and called it a hydrogen bomb because the term is so fearsome. It has always tried to frighten the world with its military might.

Should we be worried? If it is not a full-scale hydrogen bomb it adds little to the explosive power to North Korea’s nuclear arsenal, which is already worrying. The regime’s thermonuclear bark means more that its nuclear bite.

North Korea’s nuclear arsenal, its development of long-range missiles that can reach its neighbours, and its evident aim to create missiles that can reach North America are worrying, given the unpredictability of the regime.

What can we do about it? Not a lot. For a while it entered into agreements that would have prevented it becoming a nuclear power.  In 1994 it agreed to halt uranium enrichment and suspend missile tests in exchange for U.S. aid. This was at a time of famine when nearly half a million people died of malnutrition.  But North Korea ended the agreement and in 2006 it declared itself a nuclear power.

We might be able to reach an agreement to limit their arsenal and missiles, particularly if China comes on board. China supplies oil and other raw materials to North Korea, and so has some leverage. It does not want heightened tension in that part of Asia (it is happy to raise tension elsewhere) and a new famine in North Korea would mean a flood of refugees across its border. Perhaps we can persuade North Korea to limit its deterrence posture rather than aiming to be a nuclear super-power.

However, North Korea will continue to possess nuclear weapons because from the regime’s point of view, it makes sense.

The country’s leaders believe they are threatened, not with nuclear annihilation, but with political extinction, removal from the map. (Israel is in the same situation). They believe, not without reason, that South Korea and its allies would like to see the Korean peninsula united from the South, as their predecessors tried to unite it from the North in 1950 when they invaded South Korea. If that happened, North Korea would go the way of East Germany.

The regime is the most repressive, and the most ruthless in defence of its status, that the world has seen since Stalin’s Russia. It is content to see its people go hungry while it pours resources into military spending. With a population of less than 25 million, it has the world’s fifth largest standing army.

What brought down the East German regime in the end was not NATO’s nuclear arsenal but the collapse of Communism all over Europe and the evident difference in living standards with West Germany. The North Korean Government does its best to shield its people from knowledge of living conditions in its Southern neighbour.

This is the real threat to the regime, not attack by foreign armies. If they could see that, then more and bigger nuclear weapons would not be their response to their problems.

Image: AFP,

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About the author(s)...
  • Norman Moss is author of a number of well-regarded books on nuclear weapons and international affairs, whilst working as a journalist for Reuters, the Daily Mail, the Today programme on Radio 4, and other BBC outlets.
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