The Low Odds of a Sino-American Cross-Strait War

There's unlikely to be a US-China war over Taiwan

The prospect of a cross-strait war between the US and the People’s Republic of China (PRC) has come to preoccupy foreign policy observers as of late. Even though there have been several Taiwan Strait crises over the decades and even though the Communist Party has had an interest in reunification ever since the Chinese Civil War ended on the mainland in 1949, the topic of a war over Taiwan has only become widely discussed on TV in recent years. Observers who foresee a People’s Liberation Army (PLA) invasion suggest that Xi Jinping is more bellicose than his predecessors, that a war would divert domestic attention away from economic setbacks, that US deterrence relative to mainland China has become less credible, and that growing Taiwanese identity among the youth means that Beijing must act now or never to secure the island. Furthermore, commentators widely assume—or speak as if you can safely assume—that Washington will defend the ROC, at least as long as the American president’s not an isolationist. Together these notions suggest that the US and China are on a collision course over an island off the coast of East Asia. Despite all the buzz, a war between Beijing and Washington over Taiwan is unlikely.

AI-generated

China Probably Won’t Invade Taiwan

The PRC’s unlikely to launch a wanton invasion of Taiwan because the risk is intolerably high for Beijing. If it invades and fails, Taiwan will be lost forever, and this is unacceptable to Beijing since the separation from Taiwan is the final surviving legacy of their century of national humiliation.

Although people tend to simply refer to the de facto independent island democracy as Taiwan, it’s still officially the Republic of China. Both the ROC in Taipei and the PRC in Beijing agree that there’s only one China, of which Taiwan is a part; they just differ over which regime is the legitimate authority over China. However, the left-leaning Democratic Progressive Party (DPP) reigning in Taipei is warmer to the idea of Taiwan and Taiwanese as distinct from China and Chinese. In President Lai Ching-Te’s inauguration speech he remarked:

So long as we identify with Taiwan, Taiwan belongs to us all - all of the peoples of Taiwan, regardless of ethnicity, irrespective of when we arrived. Some call this land the Republic of China, some call it the Republic of China Taiwan, and some, Taiwan; but whichever of these names we ourselves or our international friends choose to call our nation, we will resonate and shine all the same. So let us overcome our differences and stride forward, with our shared aspirations, to meet the world.

This subtle assertion of Taiwan’s civic identity, separated from Han Chinese ethnicity, is reflective of the increasing separateness Taiwan’s youth feel from the mainland. In the same speech, Lai declared that the ROC would retain its system of government based on popular sovereignty and that it’s a critical contributor to the international community. Needless to say, this wasn’t taken well in Beijing.

This is all to say that Taiwan’s government and an increasing share of its citizens would probably prefer not to live under a confused status quo in which they pretend to be part of the same country as people in Shanghai. If there were an opportunity for them to be formally recognized as a sovereign country without provoking a war, they’d probably take it. However, if they were already in a war with the PRC and had a prospect of victory, they might as well declare independence, seek international recognition, and negotiate a peace deal that forces Beijing to acknowledge it. Presumably China’s leaders know this and will therefore be reticent to create a situation that enables Taipei to secede from China irrevocably. If China invades and fails, Taiwan will declare independence and reunification will forever be off the table. Beijing will thus decide to initiate hostilities if and only if the odds are decisively in its favor. Otherwise, the risk is simply excessive for what they consider to be the last open wound from the century of humiliation.

Even as the PLA modernizes and the PLAN’s expansion outpaces the other navies in the region, the odds of success for an invasion of Taiwan are unfavorable. The ROC should be doing more to deter Beijing, as conscription only lasts for six months (hardly sufficient preparation for a serious war) and defense spending hasn’t kept pace with the PRC. Nevertheless, it would still be unnervingly difficult for the PLA to successfully seize control of the island. Doing so would first require the PLA to cross the Taiwan Strait and then for it to conduct an amphibious landing. Finally, it would have to assert control over a country of 25 million people.

The first step is already a challenge due to the stopping power of water, as John Mearsheimer had labeled it. Projecting power across the sea is generally more costly and more difficult than doing so across land since such operations are more complicated and require more experience among officers to conduct and it’s more time-consuming and costly to produce naval vessels than to produce tanks and armored vehicles. Moreover, anti-access and area denial (A2AD) technology heightens the risks for offensive maritime operations in hostile waters in the modern world.

Assuming the PLAN could pull it off, they’d still have to manage to land their forces on the beaches of Taiwan. The last major amphibious landing took place in 1950 when the US Marines landed at Incheon, and that was when there was a generation of senior officers who had experience island hopping across the Pacific Ocean. Doing so on the coast of Taiwan would not only be a complicated task that no military has recent experience with, but its setting would also be restricted to a limited set of beaches. Taiwan’s coastline contains jagged formations where it would be impossible to land soldiers and vehicles, so the Taiwanese would only have to prepare heavy defenses around a predictable series of landing points.

Even if the PRC’s forces make it across the strait and land an invasion force on the island, they’d still have to sweep across it and topple or coopt the existing regime. Taiwan is a mountainous country and therefore has natural obstacles for an invader. Besides combat operations, the PLA would also have to sustain supply lines across the strait and into the island. The only country that has done this on a mass scale since 1945 has been the US. Logistics is probably the US Army’s greatest asset (interestingly the Army oversees sustainment for all the services) compared to any other ground force in the world, which is why most Western countries have outsourced their logistical needs to America. France’s operations in West Africa, Australia’s in East Timor, Britain’s in Iraq, and NATO’s in Afghanistan and Libya have all relied at least in part on US logistical capacity. While theoretically China could blockade and suffocate Taiwan if it gained dominance over the seas, it would be reluctant to do so since it considers the inhabitants its own citizens and ethnic kin, and wrecking the country would deprive it of its material and human capital.

Even If China Attacks, It’s Uncertain That the US Would Intervene

The second factor that makes a Sino-American war over Taiwan unlikely is that the US probably won’t go to war over Taiwan if China attacks. Given the risk assessment above, China is highly unlikely to launch a full-scale invasion unless Taiwan unilaterally declares independence. However, if at some point in the future the military balance between Beijing and Taipei as well as the military balance between Beijing and Washington strongly favors Beijing, the odds of unprovoked military action by the PRC become non-trivial. In that case, the risks of intervention from Washington’s perspective become greater than the risks of Chinese victory. If the US intervenes and loses, China eclipses it and gains regional primacy, which would shatter the US alliance system across the Asia-Pacific. If the US sits it out and China forcefully reunites with Taiwan, China will be emboldened and US allies will feel uncertain, but the US will not have been defeated in a hegemonic war and therefore will not have been ejected from the region. In short, China will probably only launch a wanton takeover of Taiwan if it has an exceedingly high likelihood of success, and under such conditions a US intervention would risk Washington’s entire strategic position in Asia with the odds stacked against it.

However, even without US intervention, an invasion would still be an unacceptable gamble for Beijing for the reasons outlined in the previous section (at least for now). Hence, it remains unlikely even if US intervention is improbable, and this is fortunate for Taipei because US intervention is far from certain even under present circumstances. The US and ROC signed an alliance in 1954, but the US scrapped it in 1979 upon the normalization of relations with the PRC. The US has maintained a One-China Policy since then according to which there’s one China of which Taiwan’s a part and the legitimate government is the Communist one in Beijing. Moreover, the PRC has been the recognized government of China at the UN since 1971. Ergo, neither the US nor the UN acknowledge that the ROC on Taiwan exists as a legitimate state and hence there’s no international legal basis for American intervention, which makes it unlikely that a Democratic president would intervene. NATO won’t intervene to defend the Ukraine, which has been recognized as a sovereign country by the UN, the US, and Russia itself for decades, so it’s even more far-fetched to expect that Washington would step in to protect the sovereignty of a state whose sovereignty it stopped recognizing almost half a century ago.

Some might argue that the US has far more material interests at stake in Taiwan than in the Ukraine and that its credibility would be on the line and thus it would intervene. A Republican president might feel compelled to do so on that basis since conservative statesmen tend not to be concerned with the legal grounds of military action and more preoccupied with material interests, but America already seems to be hedging by trying to develop an indigenous semiconductor industry and Taiwan’s newly adopted identity as a bastion of social liberalism isn’t going to do it any favors with Republican culture warriors.

As for the issue of credibility, the US ceased to be allies with Taiwan when it abrogated their alliance treaty in 1979. Since then, Washington has attempted to bolster the island’s security through the Taiwan Relations Act and strategic ambiguity. Under strategic ambiguity the US doesn’t make explicit whether it will or will not defend Taiwan (though Biden had a gaffe he has since backpedaled where he said the US will). The Taiwan Relations Act states that agreements between Washington and Taipei from before 1979 remain valid, but President Carter terminated the security treaty through executive action, so the principle doesn’t apply there. The Act hints that America is allowed to intervene but ultimately leaves the decision to Congress, stating:

Taiwan Relations Act - Declares it to be the policy of the United States to preserve and promote extensive, close, and friendly commercial, cultural, and other relations between the people of the United States and the people on Taiwan, as well as the people on the China mainland and all other people of the Western Pacific area. Declares that peace and stability in the area are in the political, security, and economic interests of the United States, and are matters of international concern. States that the United States decision to establish diplomatic relations with the People's Republic of China rests upon the expectation that the future of Taiwan will be determined by peaceful means and that any effort to determine the future of Taiwan by other than peaceful means, including by boycotts or embargoes is considered a threat to the peace and security of the Western Pacific area and of grave concern to the United States… shall maintain the capacity of the United States to resist any resort to force or other forms of coercion that would jeopardize the security, or social or economic system, of the people of Taiwan…

Reaffirms as a commitment of the United States the preservation of human rights of the people of Taiwan…

Directs the President to inform the Congress promptly of threats to the security or the social or economic system of the people on Taiwan, and any danger to the United States interests arising from such threats. Specifies that the President and the Congress shall determine the appropriate action in response to any such danger.

Under this uncertain posture, the US doesn’t have a commitment, and it therefore doesn’t lose credibility if it sits back to the same degree that it would if it allowed a treaty ally, such as Korea or the Philippines, to be attacked. Furthermore, the Act speaks of the need to supply Taiwan with the means to defend itself, which sounds more analogous to the US role in the Russo-Ukrainian War than to a direct intervention.

…States that the United States shall provide Taiwan with arms of a defensive character…

Declares that in furtherance of the principle of maintaining peace and stability in the Western Pacific area, the United States shall make available to Taiwan such defense articles and defense services in such quantity as may be necessary to enable Taiwan to maintain a sufficient self-defense capacity as determined by the President and the Congress. Requires such determination of Taiwan's defense needs to be reviewed by United States military authorities in connection with recommendations to the President and the Congress.

Given the low odds of an unprovoked Chinese invasion of Taiwan and the even lower odds of a US intervention in response to such an invasion, it’s improbable that there will be a cross-strait war between the US and the PRC in the coming years.