How will the DPRK nuclear crisis develop after the success of the South-North Summit on 27 April? What policies will China and the US adopt and how will they play their roles? I will attempt some analysis based on four possible scenarios.
In the first scenario, actual progress will be made in the DPRK-US dialogue, and an agreement on freezing DPRK's nuclear program will be reached. This will open the gate to multilateral dialogues in line with the dual-track approach. In such a process, the US will be critical and China must also make a significant effort.
The US has critical roles to play: making sure that the summit with the DPRK goes smoothly with an agreement to start the denuclearization dialogue; resuming denuclearization dialogue with the DPRK as soon as possible, steering it towards gradual progress and avoiding easy interruption over major differences; and persuading the DPRK to accept inspections by giving reasonable rewards such as decreasing the scale and frequency of or even suspending joint military exercises with South Korea and removing some sanctions, whilst maintaining military and diplomatic pressure.
China may also play important roles: actively supporting the US-DPRK summit and potential follow-up dialogues; supporting the US and the DPRK to first agree on targets for verifiably freezing its nuclear program and playing a positive role in the verification; supporting appropriate reduction of economic sanctions on the DPRK as a reward for freezing its nuclear program while keeping in place UN Security Council sanctions resolutions. China may also play a positive mediation role when the USA and the DPRK experience difficulty in dialogues.
In order to realize the freezing of the DPRK nuclear program, a critical question is whether there will be verification and how verification will be conducted. China will support necessary verification and favor the IAEA instead of the US in playing the leading role in verification.
Generally speaking, in the course of striving for dialogue resumption and nuclear freezing, as China and the US have shared basic objectives, the two sides have much to collaborate on even though they have their differences. Since the dialogue will be mainly between the US and the DPRK, for it to be successful, the US will obviously play a bigger role than China.
In exchange for abandoning its nuclear program, the DPRK will demand that the US fundamentally change its policy of hostility, provide the DPRK with security assurances, undertake not to overthrow its regime, and replace the armistice with a peace treaty. The DPRK will ask the US to lift sanctions, withdraw troops fully or partially, cease providing a nuclear umbrella for its allies, and establish diplomatic ties with it. The DPRK may even propose engaging in reciprocal nuclear disarmament together with the US. In short, the DPRK will ask the US for very specific and practical measures instead of an oral security assurance. On the other hand, the US wants complete, verifiable, and irreversible disarmament, before which it will not be prepared to have diplomatic ties with the DPRK or withdraw troops from the peninsula. Withdrawing its nuclear umbrella will be unacceptable to the US even if the DPRK is denuclearized. Besides, the DPRK wants to denuclearize in a phased manner and through reciprocal measures, whereas the US wants denuclearization as soon as possible and will not allow the DPRK to drag out the process.
With significant differences on how to denuclearize, it is rather predictable that freezing the DPRK nuclear program, even if possible, is still very far from North Korea abandoning nuclear weapons and establishing peninsular peace.
The American role will remain critical while the role of China will increase. As the multilateral dialogue unfolds, China will become a primary participant. If the Six-Party Talks are resumed, China may play an even greater role, including by coordinating policies of relevant parties, mitigating differences between the DPRK and the US, gradually reducing and ultimately ending sanctions against the DPRK together with the other relevant parties as denuclearization progresses, and participating in a joint security assurance for North Korea.
In the second scenario, the DPRK-US dialogue breaks up, North Korea conducts new nuclear or missile tests and the peninsular situation worsens. The US decides on limited military strikes, leading to military conflict or even war. If such a scenario unfolds, China and the US are likely to hold opposite positions but it's still possible for them to cooperate to an extent.
There are but two ways for the DPRK-US dialogue to break up. Either both parties are responsible, or just one of them is. Historically, both the US and the DPRK were to blame for previous failures. With deep mutual distrust and with the US administration very much pinned down in domestic politics, none of their previous agreements were truly implemented. As the US is the stronger party, it should probably shoulder a greater responsibility. We will see what happens this time.
If the dialogue does break up and the US makes up its mind on using military force, differences between China and the US will quickly increase. China always believes that the use of military means to resolve the nuclear issue or to interrupt the nuclear program contains enormous risks and may well lead to unbearable consequences for the Peninsula and Northeast Asia. As such, China will firmly oppose unilateral American action to use force against the DPRK.
If the US carries out limited military attacks, such as intercepting the DPRK's missile launches, destroying the missile launcher, or engaging in cyber warfare, there may be several possibilities.
First, to avoid large-scale military conflict or war, the DPRK may refrain from immediate military counterattacks and the two countries may enter a quasi-war.
Second, the DPRK may choose to wage limited counter attacks on American military assets in the ROK or Japan and the two sides will engage in a limited military conflict.
Third, as the military conflict escalates and in the face of attacks on its main military facilities by the US and its allies, the DPRK may fight back desperately with attacks on more American and ally targets within its reach. In this situation, the military conflict will quickly develop into an all-out war or even a nuclear one, which may even lead to a China-US military conflict.
In the first two cases, China will make great effort to promote dialogue so as to avoid conflict escalation or war. But if and when a war breaks out on the Peninsula and its national interests are under serious threat, including from a severe nuclear security or refugee crisis, China will have to take necessary military action to safeguard its national security.
It is predictable that in a war on the Peninsula, both China and the US will work hard to avoid another direct collision as in the previous Korean War and strive for cooperation in preventing and dealing with a nuclear crisis. In this instance in the best case scenario, a direct Sino-American military conflict and a nuclear war will be avoided. Then the war's losses may be fewer and its duration shorter, and the post-war recovery may also be shorter. Nonetheless, military conflict or war will still bring great harm to peninsular security as well as to the lives and property of people there. The flames of war may well spread beyond the peninsula.
In the worst case scenario, a nuclear war on the Korean Peninsula will bring enormous and lasting disaster and destruction to Northeast Asia at large.
In the third scenario, as the risks of war are too huge, the US and the DPRK, after failed dialogue, may fall into an even more severe military standoff, but short of conflict. In that situation, China-US relations will become even more complex and uncertain.
In this scenario the DPRK will continue nuclear weaponization by inter alia conducting more nuclear and missile tests, building more nuclear weapons and ballistic missiles and deploying them for actual combat. Relaxation and improvement of DPRK-ROK relations will not last and hostility will intensify again. To safeguard its security and that of its allies, maintain the credibility of its bilateral military alliances in the region, and prevent Japan and the ROK from going nuclear, the US will spare no effort in strengthening military deterrence against and containment of the DPRK. As such, China will have to readjust policies to safeguard its own security.
Then, two factors will influence Chinese policy and actions.
The first is the reason for dialogue breakup. If both the DPRK and the US are to blame, the relevant Chinese policy may remain basically unchanged. If the dialogue breaks up mainly because of the US, China-US cooperation on denuclearization will certainly be negatively affected whereas China-DPRK relations may improve. On the other hand, if the DPRK is to blame, China-US cooperation may be further strengthened.
The second factor is the change in American military posture on the Peninsula and in Northeast Asia after the dialogue breakup. As the peninsular situation worsens, the US will strengthen deterrence against and containment of DPRK, its military presence in the region, its nuclear umbrella for allies, and the missile defense system in the region. These kinds of moves have causes serious concerns for China in recent years. China thinks these measures target it as well as the DPRK. Now the US has publicly announced that it regards China as a primary strategic rival. Changes in its military presence in Northeast Asia, particularly development of missile defense and changing its posture of the nuclear force, will only cause greater security concerns for China and force it to take measures to prepare against it. As a result, China-US cooperation on the DPRK nuclear issue may well be undermined and an arms race in Northeast Asia may commence.
Of course, even when the peninsular situation worsens, China and the US will still have a major common interest in the denuclearization of the Peninsula. If the two sides manage their increasing differences and establish effective crisis management mechanisms, they will still be able to cooperate on pressuring DPRK through sanctions and pushing it to the negotiating table.
In the fourth scenario, the DPRK may make limited compromises (such as stopping new missile or nuclear tests, in particular ICBM test launches) and the US may tacitly recognize the DPRK's status as a nuclear weapon state, similar to India and Pakistan.
This scenario seems rather unlikely, at least for now. However, if the US focuses on the so-called 'strategic competition' from China and Russia, fights a trade war with China, or triggers another crisis across the Taiwan Straits, leading to serious deterioration in relations with China, the DPRK may well seize the opportunity to improve its relations with the US. Then the prospect of a US-DPRK compromise may occur. There are of course people making just the opposite hypothesis. They believe the DPRK will move closer towards China.
No matter which possibility becomes a reality, the DPRK gaining a status similar to that of India and Pakistan will certainly damage international cooperation on denuclearization of the Peninsula and deal a heavy blow to the international nuclear non-proliferation regime. In that case, regional security will worsen. The arms race, especially between major countries will intensify.
China will do its best to avoid such a scenario. But it's uncertain what policy the Trump administration will pursue.