Nuclear weapons are back on the agenda. There is now a greater risk of them being used than at any time since the 1960s. While we wrestle with America’s global retreat, Brexit, and dealing with Islamist terrorism, we must not lose sight of the one issue that could upend the international order and destroy our way of life.
There are now nine states with nuclear weapons. For six of them — the US, Britain, France, Israel, India and China — they are purely defensive weapons, designed solely as the ultimate means to deter attack. The remaining three think differently. Russia and Pakistan also conceive of using nuclear weapons as a means of turning a limited conflict in their favour. North Korea wants nuclear weapons to hold others at threat, both to protect the regime and to secure more practical benefits.
Nuclear weapons create a military balance where one does not exist between conventional forces. During the cold war, the Soviets had superior armed forces and Nato had to rely on the threat of nuclear retaliation to keep the peace. However skilful Russia’s use of the new weapons of hybrid warfare, the balance between regular forces is now reversed. Russia’s military doctrine also provides for battlefield nuclear weapons being used to bring a war in central Europe to an end on Russia’s terms. Its forces train for that scenario, and we have to take it seriously.
Pakistan has developed battlefield nuclear weapons as a means to defend itself. India has declared that it would respond militarily if there was another major terror attack out of Pakistan like the one in Mumbai in 2008. Knowing they would be overwhelmed by Indian forces, these weapons are Pakistan’s way to halt Indian forces shortly after they cross the border. When I was chief of MI6, I was concerned that the Indians did not understand how quickly they could cross a Pakistani nuclear tripwire. A wider nuclear exchange then becomes a real risk.
North Korea is the issue of the day. The objective of a denuclearised Korean peninsula, pursued by the previous US administrations, is no longer an achievable goal. The best that can be hoped for is the suspension of nuclear and missile testing in return for security assurances and practical aid. Sanctions are designed to draw Kim Jong Un into a negotiation with that aim, and to pressure China to take a more active part.
But it is very hard to see President Kim pulling back now. And China is more concerned about a new US-led war in Korea or the north collapsing and sending millions of refugees into China, than it is about living with a nuclear armed Pyongyang.
The US only really has two strategic options: contain and deter the threat; or destroy it, which would require regime change. There are always military options. But all who have studied the secret Pentagon plans are sobered by the scale of loss of life in South Korea these would entail. There is also a risk of China reluctantly coming to the aid of the north as it did in the 1950s.
Realistically, it seems the only practical option is containment. That requires missile defence systems to create uncertainty that nuclear-tipped missiles would ever get through to their target, and to deter any use of such weapons by being clear that North Korea would be destroyed if it ever tried to use them. Mr Kim may be hard for us to comprehend, but he is a rational actor and he is certainly not suicidal.
FT editors select the stories that explain how the nuclear threat from North Korea has escalated
US concern about this isn’t exaggerated by the Trump administration: it has a serious problem on its hands. However much we may view containment as the only sensible answer, there are still dangers of miscalculation. Mr Kim may be tempted to use his nuclear arsenal to hold others to ransom.
There is also a proliferation threat. We have seen how Pyongyang has used its nuclear technology as an export earner. In 2007, the Israelis destroyed a secret nuclear reactor in the Syrian desert that had been designed and built by the North Koreans.
Is it conceivable that a future terrorist organisation might be able to obtain such a device? Unlikely. But if they had the means, then Pyongyang would be the first place to go to get it. Pakistan’s ambivalent relationship with terrorist organisations adds to the dangers.
One country where our nuclear weapons concerns had eased is Iran. The nuclear agreement has its weaknesses, especially that it only applies for 10 years. But it is worth having, and Tehran is complying by its technical requirements. If Donald Trump walks from the nuclear deal — as he threatened at the UN last week — then before long he could find he has another North Korea to deal with, this one in the Gulf.
The outlook on nuclear weapons might look grim. But as we showed in the cold war, these issues are manageable with skilful diplomacy and the right investments in defence. We just have to give it the right degree of priority.
When I was at MI6, and before that our negotiator with Iran on its nuclear programme, I was always mindful of the nuclear threat. The only issue that can seriously threaten our way of life must be among our top international security priorities.
The writer is chairman of Macro Advisory Partners and a former chief of MI6, the British Secret Intelligence Service
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