The trust that kept nuclear armageddon at bay has eroded
On Sunday, North Korea exploded its biggest nuclear bomb, opening the possibility that it could soon target cities in the United States with a missile carrying a warhead 10 times more destructive than the one dropped on Hiroshima in 1945. Since then diplomats have failed to find a way to defuse the crisis, with Washington demanding crippling sanctions on the North Korean regime, and China and Russia calling for talks.
The stand-off seems beyond resolution, and the next North Korean provocation could potentially lead to nuclear catastrophe.
The international community was not always so hamstrung. It is worth remembering that from the 1950s to the 1970s many countries were actively developing nuclear weapons. The list makes surprising reading today. It included Argentina and Brazil, Sweden and Switzerland, as well as Taiwan and South Korea.
Those long forgotten nuclear programmes were all abandoned under US pressure. South Korea dropped its plans in exchange for a US guarantee, the so-called “nuclear umbrella”. Taiwan was forced to stop because Washington thought it would provoke China.
All this was possible because of the very specific circumstances of the Cold War. The two superpowers could agree on little apart from one thing: that nuclear weapons should be restricted to a small club. Because of the intense competition between America and the Soviet Union, a US ally at that time could trust that Washington would defend South Korea against attack from the north, as it had done in the 1950s.
South Africa even dismantled its arsenal of six completed nuclear bombs in 1989, and Latin American countries declared a nuclear weapons free zone.
It was not all quite so straightforward. One country was allowed to defy the nuclear rule: So long as Israel never publicly confirmed its nuclear capability, it was allowed to maintain a deterrent. In 1981 the Israeli air force destroyed the French-built Osirak reactor in Iraq, dealing a terminal blow to Iraqi nuclear weapons plans.
But in general the Cold War was a time when treaty-based restrictions on the spread of nuclear weapons were effective. This was due to the 1970 nuclear Non-Proliferation Treaty, one of the most successful arms control treaties in history. The NPT limited nuclear weapons to the US, the Soviet Union, France, China and Britain in return for these states pursuing nuclear disarmament with the ultimate aim of eliminating their arsenals.
But this condition remained a dead letter, allowing India to accuse nuclear weapons states of being in breach of their obligations. New Delhi became a nuclear weapons power in 1998, closely followed by Pakistan.
The control regime which applied during the Cold War has weakened in other ways. When Washington and Moscow were seconds away from destroying each other, a nuclear guarantee was a serious thing: countries in western Europe trusted the US to keep them safe, as did other allies such as Australia, South Korea and Japan.
Looking back at this time, it seems a bizarrely altruistic promise on the part of the Americans. Why would a US president sacrifice Chicago or New York to save Paris or Hamburg?
Donald Trump blasted a hole in this doctrine during the election campaign, suggesting that South Korea and Japan should have their own nuclear weapons. Once he said that, the belief system that had underpinned the nuclear umbrella began to crumble.
America already appeared weakened, after the economic crisis of 2007 and the failed military interventions in Afghanistan and Iraq. Now Mr Trump was airing opinions that others had only thought about in private. If the guiding principle of the United States was “America First”, then the nuclear umbrella was full of holes.
The effects of this change of perception can be seen in the new South Korean President, Moon Jae-in. Rather than holding Mr Trump close as he might have done in the past, he is openly at odds with the US president’s bellicosity, calling instead for talks with North Korea.
Even more significant is the fact that the site of the nuclear crisis is China’s neighbour and its originator a fellow communist state. Unlike in the Cold War, when two superpowers came to a series of understandings which blunted their rivalry, China is a disruptive rising state. It has no aspirations to global leadership, but it has very clear ideas about the role it sees for itself in north-east Asia, which requires the US to back off.
Beijing is thus unlikely to bow to US demands to cut off oil supplies and thus bring the North Korean regime to its knees. This is not on account of any love for Kim Jong-un: by all accounts he is viewed in Beijing as an unruly neighbour, and despite their formal alliance, relations are chilly.
China seems ready to swallow Kim’s provocations because America is the strategic rival – they fought a war in the 1950s in the Korean peninsula – and the Communist Party cannot afford to lose face by teaming up with an unpredictable US president against an ally.
Read Con Coughlin's view on the North Korean crisis
Regrettably, there is no basis of trust between the US and China to achieve a diplomatic solution. That is not so say that there is no solution possible. If the US backed down from its position that it will not speak to North Korea while it is developing nuclear weapons, accepted the Kim regime as legitimate and ended military exercises in South Korea, one can imagine that the Chinese would step forward to keep their ally under control.
But this would be a huge retreat for America, whose forces would disappear over the horizon into the Pacific. All the countries in the region would understand that China was the rising power and the US was in decline in north-east Asia. And what about restricting the spread of nuclear weapons? Nuclear blackmail would be shown to work. It would mark a return to the free-for-all of the 1960s when even peace-loving countries believed that security depended on a nuclear strike force. That would be the most damaging consequence of this crisis.
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