Sanctions and wild threats will not end North Korea’s nuclear programme; Washington should consider how to contain a nuclear-armed Pyongyang. Matthew Cottee predicts a prolonged and uncomfortable standoff.

Kim Jong-Un looking at a metal casing

By Matthew Cottee, Research Associate, Non-proliferation and Nuclear Policy

North Korea conducted its sixth and most powerful nuclear test on 3 September. The latest in a line of provocations, the nuclear test was not a surprise; the increased yield was also to be expected. Although claims of a thermonuclear device were thought to be exaggerated last time a test took place in September 2016, the predicted yield of Sunday’s device is estimated to be in the range of 100-300 kilotons. Irrespective of whether the device is a staged thermonuclear design rather than a more basic fission weapon—as was suggested by a conveniently timed North Korean media release displaying a peanut-shaped object—the yield of North Korea’s current design is suitably large.

Despite a much improved yield, the nuclear test does not significantly alter the overarching strategic calculus. This should not be a new capability that foreign governments had failed to plan for. What has changed since the last nuclear test, however, is the US administration’s response. In September 2016 after the fifth nuclear test, then President Barack Obama promised to “put some of the toughest pressure North Korea has ever been under as a consequence of this behaviour. Can I guarantee that it works? No. But it's the best option that we have available to us right now and we will continue to explore with all parties involved — including China — the means by which we can bring about a change in behavior." There was no mention of military action.

Trump lashes out at North Korea - and its neighbours

After leaving office, Obama’s approach was criticised for being too passive. In contrast, following Pyongyang’s threats against the US territory of Guam, President Trump was criticised for his use of improvised and bellicose language. The US was “locked and loaded”, ready to respond with “fire and fury”, echoing the kind of rhetoric you might expect to hear from a combat arcade game. This time, the language was toned down, but the sentiment was similarly controversial. Trump publicly questioned South Korea’s approach, undermined China and threatened to cut all trade with states doing business with North Korea. At a time when alliances and key relationships should be paramount, Trump instead criticised partners’ efforts.  

Trump’s officials have usually checked their president’s bluster with a more consistent message, but the words of Defense Secretary James Mattis on this occasion were less reassuring. He has previously stated his desire to find a diplomatic solution to the crisis, but his comments in reaction to the nuclear test were very firm: "Any threat to the United States or its territories - including Guam - or our allies will be met with a massive military response, a response both effective and overwhelming." He caveated by explaining that the US was “not looking to the total annihilation of a country, namely North Korea".

The more aggressive signalling is, to an extent, understandable. Throughout this period of heightened activity, missile tests have constantly prompted the question of what comes next in terms of policy responses. How could the international community escalate its reaction? With seemingly no answers, the UN Security Council has been the option of last resort, passing more sanctions and rhetorical condemnation.

This will likely happen again, but unless they target the supply of highly specific rocket fuel, for example, more sanctions will do little to check a nuclear and missile programme that has already achieved significant gains. Trump’s threat of cutting trade with states doing business with Pyongyang was impractical, costly and ineffective; doing so would hurt the US economy more than it will impact North Korea. China is North Korea’s main trading partner, but has no intention of seeing the Kim Jong-un regime fall. Maintaining a status quo suits Beijing; it should not be relied upon to exert the economic leverage being asked of it. Nor does it have the influence that many assume. The fact that the sixth nuclear test occurred in the lead up to China’s important Communist Party Congress, scheduled for next month, suggests North Korea is less interested in how Beijing will react.

US should ask how it will contain a nuclear-armed North Korea

Ultimately, China cannot address Pyongyang’s primary security concern: US military might and potential push for regime change. Although a difficult concept to sell, the US should perhaps prepare for a situation in which North Korea is informally accepted as a nuclear weapons state. Washington should start thinking about what a strategic relationship with adversaries in Pyongyang might look like; how it might be managed and how North Korea might be contained. This would require Trump to walk back on his promise that the development of an ICBM ‘won’t happen’, but a window for dialogue and negotiation may open once North Korea feels comfortable with its strategic capabilities. This might include a reliable, operational and nuclear-capable intercontinental ballistic missile that can hit the continental United States. At that point, there may be scope to discuss a freeze on further development of capabilities, such as multiple independently targetable re-entry vehicles (MIRVs) or decoys, designed to provide more firepower and bypass missile defence systems, respectively.

What North Korea might seek in return remains an open question. An end to joint US-ROK military drills? A restructuring of US forces in the region? The US will expect a lot more in return for such concessions. One issue that definitely will not be on the table from North Korea’s perspective is denuclearisation. Kim Jong-un perceives nuclear weapons as his guarantor of survival, both domestically and internationally. Having spent so much, in all senses, on their recent development, they will not be given up.

None of this will be palatable to the US and there is now a sense that a reckoning is nigh. Given the increasing pressure on the US administration to do something—anything—some unilateral action cannot be completely ruled out. Although a quick fix, military attacks against North Korean targets would be catastrophic for the region and beyond. Barring war, however, we are set for a prolonged and uncomfortable standoff.

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