The Taiwan Strait After a Second Korean War

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The Taiwan Strait After a Second Korean War

The end of the Kim regime would spell trouble for the Taiwan Strait.

The Taiwan Strait After a Second Korean War

Soldiers from Taiwan’s special forces move past colored smoke during a helicopter landing training and all-out defense demonstration in Taipei, Taiwan (Dec. 14, 2017).

Credit: AP Photo/Chiang Ying-ying

One year after the election of Donald Trump, most Asia experts have breathed a sigh of relief that the new administration’s Asia policy has been marked by more signs of continuity than change.

Despite a stridently nationalistic “America First” tone, and repeated statements on the campaign trail regarding the status of U.S. allies in the Pacific, the administration has largely settled on a traditionalist policy in East Asia. This has been punctuated with tougher talk on trade, but little action.

Even Kim Jong-un’s ramping up of North Korean nuclear testing has accentuated this continuity, despite the contentious tweeting of the commander-in-chief; the administration has repeatedly re-assured U.S. allies South Korea and Japan, while quietly dropping demands for increased host nation payment for U.S. defense. The feared volatility and unpredictability of the president has not translated into policy. This relative policy consistency has paid off in continued stability of U.S. alliance relations, allowing the administration to credibly accuse North Korea of raising tensions in Northeast Asia.

One unexpected side effect to the nuclear crisis has been a dampening of tensions elsewhere in the Indo-Pacific. With the prospect for a nuclear catastrophe on the Korean peninsula, other crises or potential conflicts, such as the disputes over the Senkakus or the South China Sea, have receded in urgency.

Ironically, this is a good indication that the end of the Kim regime and a collapse of the North Korean state would result in increased tensions between the United States and China.

While there have been many studies looking at how North Korea, South Korea, and the United States could end up in war, and many studies of how such a war would play out, there has been little attention paid to the security landscape post-crisis.

While scenarios of a North Korean collapse play out in vastly different ways, the overall end result would be relatively similar: millions of refugees streaming to China and South Korea. With a war scenario, this would happen in the context of a devastated Seoul, which by itself represents almost 50 percent of South Korea’s GDP.

In the short term, the economic devastation from either scenario would absorb enormous resources and attention from South Korea, China, and the United States, which would serve to lower tensions for a time. However, over the long term, the end result would likely be an East Asia with fewer mitigating factors to a conflict between the United States and China. The worst of the flashpoints would likely be the original Asian security crisis, the Taiwan Strait.

United States

Even with the devastation of a new Korean War, the United States would almost certainly come to the aid of Taiwan if a cross-strait conflict were to occur, especially with PRC provocation. The White House has signaled the traditional U.S. commitment to Taiwan in multiple ways: for instance, Trump accepted Taiwan President Tsai Ing-wen’s congratulatory telephone call following his election, but before his inauguration. More recently Tsai was permitted to stop in Hawaii on a tour of the islands of the Pacific. On the policy side, the administration continues to refuse to rule out arms sales to Taiwan; has allowed Taipei’s entry into the Global Entry Program; and nominated a pro-Taiwan scholar, Randy Schriver, for the position of assistant secretary of defense for the Asia-Pacific. This has been coupled with a historically pro-Taiwan U.S. Congress and a vocal Taiwan lobby, both of which have remained undiminished due to continued hamfisted Chinese attempts at global public influence.

The expected U.S. response to a new Korean War would, as a byproduct, increase bilateral tensions with China. The United States has for many years sought to increase the balance of its military force in Asia from 55 percent to 60 percent of total assets, but a contingency on the Korean peninsula would result in an influx of U.S. military assets into the region — assets that would likely continue to remain given the heightened tensions following a war. What would change would be how these assets would be positioned; instead of a concentration in South Korea, there would likely be re-deployment across the entire Asia-Pacific, significantly complicating Chinese military targeting and worrying Chinese political leadership.


Under President Xi Jinping, Chinese political leadership is in its most centralized state since the days of Mao. While this allows for expedited decision-making, the personalization of rule creates an overriding imperative for Xi to avoid disorder and the perception of having backed down on the world stage.

These interrelated factors would come into play in the chaos following the fall of the Kim regime, which would be the most significant domestic and foreign policy challenge for the Chinese Communist Party since the Tiananmen Square massacre. The most immediate concern would be millions of North Korean refugees streaming into China, causing extremely negative consequences for the population of Northeast China.

This severe socio-economic disruption would certainly lead to an aggravation of relations between the United States, China, and the newly unified Korea, especially if Chinese leadership felt that an aggressive U.S. policy was the catalyst for the war. Beijing would be occupied for a time by internal and external disorder resulting from a war in Korea, but after overcoming one of its most severe geopolitical nightmares, China would likely emerge more confident and confrontational.

These tensions would reflect on the China-Taiwan relationship. Under Xi, China has already taken a harder line against Taiwan, due to a perceived shift in economic strength. Following the 19th Party Congress, Xi has made it clear that the Taiwan question would not be put off indefinitely, and strongly hinted that reunification would be considered part of China’s “great rejuvenation,” which is supposed to be complete by 2049.


The fall of the Kim regime and reunification along South Korean lines would drastically reconfigure Korean foreign policy. Over several decades, a reunified and economically resurgent post-conflict Korea would mean a country of 75 million with a significantly larger economic base to compete globally. An apt historical corollary would be that of Germany following the reunification of the East and West in 1991. In the European example, a larger economic base and political heft allowed Berlin to become the predominant power in the European Union, fundamentally altering the economic and political balance of the European community.

For the China-Korea relationship, this would result in a relationship fraught with tensions. These would range from old historical issues such as Chinese claims on parts of North Korea and past Chinese support for the Kim regime, to new geopolitical challenges such as the status of U.S. basing in Korea, a shared border, and economic tensions.

Korean relations with the United States and Japan would also be reconfigured. Without the threat of North Korea, the U.S.-Korea alliance would face tensions regarding its purpose, much like what NATO went through following the fall of the USSR. The nascent cooperation with Japan against the North Korean threat would dissolve, and a traditionally nationalistic Korean populace will seek a more hawkish foreign policy against this historical adversary.

Against the backdrop of rising regional tensions, the reunified Korea would be reluctant for American military assets in their territory to be used against China in a Taiwan contingency. This hesitancy would likely allow China to perceive the Korean border as a “secure front,” and so would be able to shift resources from that border to the regions adjacent to Taiwan.


Japan’s geopolitical environment would be significantly altered by a conflict in Korea. Similar to South Korea, in the short term Japan would see significant economic devastation. The Kim regime would almost certainly launch missiles against Japan, and the war would devastate Japan’s roughly $100 billion annual trade with South Korea. Over the long-term, though, Tokyo’s foreign policy would become more active as resources could be re-deployed from the now non-existent North Korea threat. Unlike reunified Korea, which would probably look to hedge their bets between China and the United States, Japan would likely wish to solidify its alliance with Washington — to protect against both China as well as a resurgent Korea. Moreover, Japan and China have long engaged in a quiet diplomatic and economic competition for influence throughout the Indo-Pacific, and as both nations become more active abroad, their agendas will increasingly clash.

Tokyo will continue to have a strong interest in ensuring the de facto independence of Taiwan. The populations of both countries hold very favorable impressions of one another as indicated in two recent surveys, with a significant volume of bilateral trade. Japan also has a strong interest in ensuring that China would not be able to establish military bases in Taiwan, which would threaten Japan’s hold on the Senkaku islands and severely reduce the capability of the Japanese/U.S. militaries to monitor the ever-growing Chinese navy. Finally, Japan fully recognizes that in a Taiwan scenario, China would likely not hesitate to strike at American assets based on Japanese soil — whether or not the Japanese actively join. Japan would almost certainly view a Chinese attack on American assets in their nation as an act of war. Additionally, under the Abe administration, Japan has joined the growing list of nations in Asia that are investing large sums into military modernization to balance against the People’s Liberation Army’s rapid qualitative advancement — something that will continue to accelerate even after a new Korean conflict.


Out of all the regional powers, Taipei would likely be the only player to emerge physically unscathed from a Korean conflict. There would be significant economic disruption as the war would badly hurt Taiwan’s trade with South Korea and Japan, but as Taiwan largely depends on China and the United States for most of its trade, the effects would be more muted than the other powers.

Both Korea and Japan would seek to expand their unofficial relationship with Taiwan, as both powers would seek to balance against the Chinese desire for hegemony in East Asia. Taipei would eagerly accept the increased recognition and international space, and would likely expand upon Tsai’s signature New Southbound Policy, meant to diversify Taipei’s trading partnerships and reduce its dependence on the PRC. Moreover, Taiwan would also increase military spending, in a continuation of current trends.

All of these actions would be heavily opposed by China, and would significantly increase tensions in the region.

Be Careful What You Wish For

The unpredictability of the Kim regime and its drive for nuclear weapons is widely acknowledged to be the greatest threat to regional peace in Asia today. With the North Korean development of viable ICBMs, this threat extends to the United States. This development, combined with the fall of the Islamic State, has rapidly focused the attention of US foreign policy on Korea.

A change in U.S. foreign policy to crisis management with China would almost certainly mean an increase in tensions between the entire U.S. alliance network and China. Each partner must confront their own unique challenges as Beijing’s geopolitical ascent sends shockwaves through the international system.

The U.S. alliance system in East Asia already faces numerous challenges, most of which arose on an individualized basis. These include Japan’s moves toward military normalization; the growing cross-strait military imbalance; and the increasingly unpredictable nature of U.S. foreign policy. As China’s relationship with outside powers becomes increasingly complex, these points of conflict, once isolated, are becoming increasingly interwoven and inseparable.

Recently, Washington’s focus has been primarily on immediate crisis management on the Korean peninsula, in the form of either de facto containment of North Korea or a war and its aftermath. There has been comparatively little focus on potential medium- to long-term post-war scenarios, and how that may affect U.S. relations in the region. U.S. leadership must consider these scenarios in developing the foreign policy of today, or this particular form of blindness could mean the replacement of brinksmanship with an impoverished North Korea to brinksmanship with a resurgent China.

Eric Chan is an international affairs specialist for the U.S. Air Force, with a focus on Chinese political and security issues.

Peter Loftus is a U.S. Air Force officer and a graduate of the Johns Hopkins School of Advanced International Studies where he focused on East Asian security issues.

The opinions expressed here are those of the authors alone and do not represent the views of the Department of Defense or the U.S. Air Force.