2018年9月20日，韩国总统文在寅（中、右）和朝鲜领导人金正恩（中、左）访问位于朝中边境的朝鲜半岛最高峰白头山。（平壤新闻社）（共同社）

尽管朝鲜本月早些时候炸毁了与韩国的联络办公室，但金正恩在6月24日宣布，平壤将暂停其计划不明的军事行动，这使朝鲜和平进程得到暂时的喘息。朝鲜前几个月的挑衅行为包括威胁加强核潜力、发射短程导弹的次数创单月最高纪录，以及叫停与韩国的各种信任与安全共建措施。

朝鲜公开表达愤怒的焦点，是韩国政府未能抑制朝方叛逃者在边界一带进行煽动，未能减少掣肘朝韩重要经济项目的制裁措施。平壤或许还试图扩大韩国与美国的分歧。内部因素，如统治阶层内部的政治把戏，以及新冠疫情带给朝鲜当局的压力，可能也是平壤躁动的原因。

目前还不清楚挑衅行动的暂停会持续多久。金正恩也许更希望特朗普继续执政，而不是面对一个新的美国政府，因为这个新政府也许会像之前的新总统班子一样放弃最近的谈判，对政策进行冗长的复审，然后朝一个全新的方向前进。无论怎样，中国和美国的政策制定者必须随时准备应对严峻的紧张局势。

不管是什么原因，朝鲜和平进程的挫败，都将严重损害中美两国重要的国家利益。朝韩关系的缓和对中美两国都有好处，最重要的是朝鲜停止了引爆核装置和发射远程导弹。这个国家总是利用核武器获取让步，对北京和华盛顿进行两头讹诈。

特朗普政府支持韩国总统文在寅的和平倡议，同时对平壤实施了开放的外交政策。2017年6月的韩美联合声明支持同朝鲜对话。2018年6月的朝美新加坡峰会声明也支持朝韩改善关系。美国官员表示，这些声明及美国的总体政策，都是希望用某种和平机制推动裁军和地区安全。

然而，近期危机中的一个刺激性因素是，它发生在冷战以来中美关系最坏的时候。北京和华盛顿之间紧张局势的不断升级，助长了平壤利用中美分歧。最糟的情况是，在朝鲜战争爆发75年之后，这些分歧促使朝鲜采取行动，进而导致中美两国再次兵戎相见。

多年来，中美在朝鲜问题上的合作一直起起伏伏。2018年，在特朗普和金正恩打了一年嘴仗之后，在特朗普的私人外交，以及中国的干预下，平壤暂停了它的核及远程导弹试验。自那时以来，中方的压力帮助阻止了朝鲜恢复核或洲际弹道导弹试验。总体上说，中国官方支持特朗普缓和朝美紧张关系的外交行动，但它希望华盛顿为无核化提供更多的激励措施。此外，尽管北京支持恢复包括俄罗斯和日本在内的六方会谈（最后一次会谈是在十年前），但华盛顿对这种形式已经失去了兴趣。

冷战时期，中国曾经作为重要的意识形态伙伴同朝鲜结盟。现在，北京的一些人可能认为，华盛顿和平壤之间的紧张关系有助于分散五角大楼对中国的注意力，有助于让中国在与韩美的地缘政治竞争中取得优势，并在许多问题上为北京增加与两国打交道的谈判筹码。

朝鲜的行动还没有达到从前军事挑衅的水平。就在2010年，朝鲜武装部队轰炸了韩国的延坪岛，击沉一艘韩国护卫舰。这种行动如果今天再发生，可能会导致另一场战争。无论是拆除坐落在朝鲜境内的联络办公室，还是中止《全面军事协定》，或是朝鲜上个月的任何行动，都没有在朝韩分界线两侧造成任何伤亡。

尽管如此，朝鲜的威胁使文在寅目前很难有借口既减少制裁，又不显得软弱。如果中国的行为让朝鲜再次作出误判，新的武装对抗就可能发生。与2010年不同，韩国军方已经准备强力反制朝鲜的武装袭击。事态不断升级将使半岛再燃战火，从而可能把中美拖入数十年来的第一次正面武装冲突。

无论是北京还是华盛顿，都无法对一向我行我素的朝鲜领导人施加太大影响。由于中美关系紧张，双方很难采取强有力的联合行动。不过，两国采取平行的单边行动，加上韩国和其他国家的支持，将有助于避免半岛和平遭到不可挽回的破坏。

例如，中国可以更好地执行联合国对朝鲜的制裁，让朝鲜领导人更有动力参加谈判。联合国专家小组发现，在阻止朝鲜与外国船只在中国近海非法转运违禁物品方面，中国的一些机构存在松懈。

同时，美国应考虑允许扩大对朝鲜的人道主义救济，以解决中国对朝鲜因新冠疫情陷入极度困难和出现动荡的担忧。由于美国和其他国家的制裁，与几年前相比，韩国对朝鲜的人道主义援助已大为减少。

新冠危机自然而然地使北京和华盛顿把注意力放在了其他事情上。希望最近的事件提醒中美两国官员，就算金正恩从人们的视野中神秘消失数周，另一场朝鲜战争的威胁也不会消失。

South Korean President Moon Jae In (C,R) and North Korean leader Kim Jong Un (C,L) visit Mt. Paektu, the highest peak on the Korean Peninsula on the North Korean-Chinese border, on Sept. 20, 2018. (Pyeongyang Press Corps)(Kyodo)

Despite North Korea demolishing its joint liaison office with South Korea earlier this month, the June 24 announcement by Kim Jong-un that Pyongyang will suspend its unspecified planned military actions has given the Korean peace process a temporary reprieve. The DPRK provocations of previous months included threats to fortify DPRK's nuclear potential, a record number of monthly short-range DPRK missile launches, and the suspension of various joint confidence-building and security measures with the Republic of Korea.

The North's public ire has been focused on the ROK government's failure to suppress DPRK defector agitation along the border and curtail sanctions blocking major inter-Korean economic projects. Pyongyang may also be seeking to widen differences between South Korea and the United States. Internal factors—such as political manoeuvring within the ruling elite and the strain on the DPRK regime due to the COVID pandemic—may also account for Pyongyang's incitements.

It is unclear how long the current provocation pause may last. Kim may prefer that Trump remains in office, rather than confront a new U.S. administration that, like previous new presidential teams, could discard recent negotiations, undertake a lengthy policy review, and then strike out in an entirely novel direction. Nonetheless, Chinese and U.S. policymakers must prepare for serious tensions at any time.

Whatever its causes, a breakdown in the Korean peace process will substantially damage Chinese and U.S. vital national interests. Both China and the United States have benefitted from the reduced inter-Korean relations. Most importantly, the DPRK has ceased detonating nuclear devices and launching long-range missiles. The DPRK uses nuclear weapons to extract concessions and blackmail Beijing as well as Washington.

The Trump Administration has supported ROK President Moon Jae-in's peace initiatives while simultaneously pursuing its own diplomatic opening with Pyongyang. The June 2017 ROK-U.S. joint statement endorsed dialogue with the DPRK. The June 2018 DPRK-U.S. Singapore summit declaration also backed better inter-Korean relations. U.S. officials have argued that these and other statements, as well as U.S. policies in general, presume some kind of peace regime to facilitate disarmament and regional security.

Yet, an aggravating factor in the recent crisis has been that it has occurred during the worst deterioration of Sino-American relations since the Cold War. The escalating tensions between Beijing and Washington encourage Pyongyang to exploit these differences. At worst, they could facilitate Northern actions that lead to renewed conflict between China and the United States, 75 years after the anniversary of the onset of the Korean War.

Sino-U.S. cooperation regarding North Korea has waxed and waned over the years. In 2018, following a year of inflammatory rhetorical exchanges between Trump and Kim, Trump's personal diplomacy combined with Chinese intervention induced Pyongyang to suspend its nuclear and long-range missile tests. Since then, PRC pressure has helped discourage the DPRK from resuming its nuclear or ICBM tests. Chinese officials have generally backed Trump's diplomacy for reducing DPRK-U.S. tensions, but have wanted Washington to offer more incentives for denuclearization. Furthermore, though Beijing favors resuming Six-Party Talks that also include Russia and Japan, which were last conducted over 10 years ago, Washington has lost interest in the format.

During the Cold War, the PRC aligned with the DPRK as an important ideological partner. Now, some in Beijing may see the tensions between Washington and Pyongyang as helpful for distracting the Pentagon from concentrating against China, giving an advantage to the PRC in its geopolitical competition with South Korea and the United States, and as generating negotiating leverage for Beijing with both countries on many issues.

The DPRK's actions have not yet risen to the level of previous military provocations. As recently as 2010, the North Korean armed forces bombarded the ROK's Yeonpyeong Island and sank a ROK corvette—actions that if repeated today could lead to another war. Neither the demolition of the joint liaison office, which was located wholly on DPRK territory, nor the suspension of the Comprehensive Military Agreement nor any other Northern action last month generated any casualties on either side of the inter-Korean border. .

Nonetheless, the DPRK threats have made it difficult for Moon to justify sanctions relief now without looking weak. If PRC actions lead to renewed DPRK miscalculations, there is potential for renewed armed confrontations. Unlike in 2010, the ROK military is prepared to respond to DPRK armed attacks with strong counteractions. Escalatory dynamics could trigger renewed war on the Peninsula, with the risk of dragging China and the United States into their first direct armed clash in decades.

Neither Beijing nor Washington can exert much influence on the perennially unruly DPRK leadership. Strong joint action will prove difficult due to Chinese-U.S. tensions. However, both countries can pursue parallel unilateral actions that, along with the support of South Korea and other countries, can help avert an irreparable breakdown of peace on the Korean Peninsula.

For instance, China could give the DPRK leadership more incentives to negotiate by enforcing UN sanctions against North Korea better. The UN Panel of Experts has found that some PRC authorities have been lax in impeding illicit transfers of banned goods between North Korean and foreign ships in waters near China.

Meanwhile, the United States should consider allowing expanded humanitarian relief to the DPRK to address Chinese concerns about undue suffering and instability in the DPRK due to the COVID-19 pandemic. The U.S. and other sanctions have substantially reduced ROK humanitarian aid to the North compared with earlier years.

The COVID-19 crisis has naturally focused Beijing's and Washington's attention on other issues. Recent events should hopefully remind Chinese and U.S. officials that, even if Kim mysteriously disappears from view for weeks on end, the threat of another Korean War does not.