U.S.-China War Scenarios: Risks, Strategies, and Global Implications

Could the United States and China really go to war? Who would win?

Here’s something most Americans may be surprised to hear: military strategists in the United States consider China the nation’s main military worry—with the distinct possibility of a major U.S.-China war in the years to come. That is a terrifying prospect. The two countries are the world’s top two economic and military powers, both armed with nuclear weapons, each contributing 15% to 20% to world gross domestic product, and each dependent on the other for its prosperity given the depth and breadth of their economic relationships. Were they to go to war, however, global prosperity might soon become the least of our concerns; World War III could not be ruled out, and the survival of the human race might even be on the line.

A quick word of partial reassurance: I think that American military strategists tend to be, on average, slightly too hawkish on China, a country that some are calling part of a “new axis of evil” that also includes Russia, North Korea, and Iran. I might agree that the latter three nations, or at least their current leaderships, should be viewed as fundamentally malevolent and dangerous. But China is a more complex case, having brought hundreds of millions of people out of poverty in recent decades, having done much for economic growth around the world in general, and showing a certain aversion to military risk (it has not gone to war since 1979, though it has skirmished against India and the Philippines in recent times). Perhaps military strategists are seeing things too darkly, even as they rightly sound the alarm on some of China’s behaviors as well as its growing capacities and the ensuing risks to American interests. This backgrounder sketches out three different ways in which war pitting the People’s Republic of China against the United States (and some number of its allies) might break out¹:

1. Over disputed islets and waters in the Western Pacific.
2. With a Chinese attempt to invade and conquer Taiwan, a polity of 23 million people that Beijing considers a renegade province, followed by a U.S. decision to come to Taiwan’s aid.
3. With a more limited use of Chinese force against Taiwan, most likely involving some type of blockade of the island in an attempt to strangle and coerce it into capitulation and reunification.

I find the first scenario the most likely to erupt, but the least likely to lead to all-out war. The last scenario causes me the greatest angst, based on a combined sense of its likelihood together with its potential for escalation both in the likely geographic zone of conflict and the potential use of nuclear weapons.

Limited war in the Pacific: The South China Sea

One set of scenarios has become all too plausible in recent years: a skirmish between the Philippines and China as they pursue competing claims to certain islands, rocks, and other generally inconsequential features in the South China Sea. The problem is that ownership of even rather small islands can provide land for military bases, while also conferring large territorial seas and exclusive economic zones to the country able to establish possession. On top of that, China seems to want to control ship movements throughout the entire South China Sea, or at least maintain the right to veto those it doesn’t like (such as those involving American aircraft carriers). A land formation called the Second Thomas Shoal is the most acute problem now; Manila (the capital of the Philippines) deliberately stranded an old ship on the shoal 25 years ago to assert its claim and keeps military personnel there all the time. In 2016, an Arbitral Tribunal constituted under the 1982 U.N. Convention on the Law of the Sea ruled in the Philippines’ favor given the proximity of inhabited Filipino islands to the shoal (meaning that the shoal is technically within the Philippines’ exclusive economic zone). But Beijing rejects that argument. The United States has not ratified the convention upon which the tribunal based its decision, though it tends to accept its logic.

China has sometimes tried to impede the resupply of the Philippines’ position. Earlier this year when it did so, two ships collided, and a Filipino sailor lost his thumb. Filipino President Ferdinand Marcos, Jr. had earlier stated that were a Filipino to lose his or her life in such a future showdown, that could be seen as an act of war. The problem would be significant enough if it involved only China and another regional country (there are others in the region besides the Philippines mired in disputes with China over the ownership of various islands). But because the United States has a security treaty with the Philippines, it could feel obliged to intercede in defense of its ally in the event of an escalating crisis in the future, though the exact threshold of violence that would lead to American intervention has not been specified, nor of course has the nature or scale of any such hypothetical intervention.

The United States, in the event of worsening tensions, would probably have only a few options:

• Accompany a future Filipino resupply ship to the shoal and hope that China would choose not to press the issue.
• Shoot back at any Chinese ship that shot at Filipino or American vessels.
• Place its own personnel, at Filipino invitation, on the shoal and make it clear it will not only resupply them but defend them.
• Choose a non-military punishment of China, most likely in the economic realm.

Fortunately, none of these options seem likely to lead to all-out war, since it would be the height of irrationality and irresponsibility to let such a skirmish blow up into a major confrontation. Unfortunately, however, once the shooting starts and people start dying, it is hard to rule out worrisome escalatory dynamics. Most wars in human history are not accidental, but sometimes big wars do get sparked by small events, as with the assassination of the archduke of Austria-Hungary in Bosnia in June 1914, leading to World War I that August.

An attempted Chinese invasion of Taiwan

Might China, tired of waiting for reunification since 1949 (when the Communist Party won China’s civil war, and the losing Nationalists fled to Taiwan) invade the island to force its absorption into the mainland? Once done, it would be very hard to undo, to say the least (though the United States might support resistance forces in Taiwan even if China managed to get its military ashore in an attempt to control the island).

It would also be extremely dangerous for the region and the world because of the risk that the United States would respond militarily. The United States no longer has any treaty obligation to come to Taiwan’s defense, as it did before Henry Kissinger and Richard Nixon began the great opening to China in the 1970s. But the United States has a law known as the (1979) Taiwan Relations Act declaring that it might well do so if a Chinese attack against Taiwan occurred in an unprovoked manner. The United States has historical bonds with Taiwan, having backed the Nationalists during the civil war and then during the Cold War, and since the Eisenhower administration, Washington has threatened to use force to defend Taiwan. (In earlier eras, American maritime and air supremacy over China’s military was more lopsided than is the case today, making the task easier.) The United States has economic reasons to defend Taiwan, given that most of the world’s best semiconductor chips are made on the island. And it has strategic reasons: Taiwan’s fall could signal a China bent on regional aggression and expansionism—whatever Beijing might say now about its aims being limited to what it defines as national reunification—as well as a United States no longer as committed to the defense of friends and allies as it was once perceived to be. For these reasons, on as many as six occasions when asked, President Joe Biden has indicated an inclination to help defend Taiwan if China were to attack it (Biden gave no indication, however, about whether he would ask Congress for authorization).

The good news about deterring this war is that, for China, it would be a huge roll of the dice—and I do not detect a recklessness or acceptance of high risk in the leadership of today’s People’s Republic of China (PRC). There are, of course, different views about the nature of the China threat today, but few really argue that China would fail to carefully consider the costs and risks of any major military operation. President Xi Jinping is nationalist, assertive, and autocratic, but there is little to suggest he shares his friend Vladimir Putin’s proclivity to use force for high-risk ventures. And this one would be very risky, since amphibious assault has become even harder than during World War II, given the proliferation of sensors that can detect big troop ships and many types of precision missiles as well as torpedoes (and drones) that can strike them. With some luck, Taiwan might itself be able to fend off the attack; with prompt American military aid, it would have a very good chance.

The bad news about this scenario, however, is that the United States still largely relies on large, fixed airfields (notably on Okinawa, Japan) and big ships (notably, aircraft carriers) to provide much of the firepower that would be used to counter such an attack. It also has fragile civilian infrastructure in the United States (ports, airfields, electricity grids, fuel distribution networks) that it would need to deploy, resupply, and control many of these military forces. These may all be vulnerable to Chinese preemption. Yes, the United States has attack submarines and long-range stealth bombers too, but China may conclude that America does not have enough. The PRC might also miscalculate America’s ultimate willingness to risk World War III over what, in Beijing’s eyes, may seem a relatively minor interest to the faraway United States. In other words, Beijing might, rightly or wrongly, construct a theory of relatively rapid victory that it comes to place great stock in.

When war games are carried out to gauge how these scenarios might play out—and who might win—different games produce different results, even about the ultimate victor. Some have projected that the United States would ultimately succeed in helping Taiwan protect itself, though possibly losing many aircraft, ships, and tens of thousands of personnel in the effort. Other simulations have wound up predicting Chinese victories.

My own views can be condensed into three main points:

1. This is an extremely risky scenario for China.
2. We can make it even riskier with the right kinds of additional military investments by Taiwan and the United States—for example, unmanned or tilt-rotor aircraft operating off Okinawa’s roads that do not require runways for launch and that can deploy sensors and shooters to the Taiwan Strait in the event of an invasion attempt, and that in some cases are numerous and inexpensive enough to be expendable without jeopardizing America’s future military posture. Unmanned underwater vessels stationed permanently in the Western Pacific might play similar roles.
3. If heaven forbid the scenario takes place anyway, even if China loses at first, we are still in trouble. There is little reason to think the war will simply then end. Beijing might then consider nuclear threats or retaliation, against Taiwan and/or the United States. It might also simply settle back into what I think is its best military and strategic option in the first place: a blockade, perhaps combined with cyberattacks and other forms of harassment or limited violence. The blockade, and related operations as well as American counters, might expand geographically to the Indian Ocean, the Persian Gulf, and beyond. It is to that latter type of scenario that I now turn.
   

China’s best option: Blockade

Rather than undertake a cosmic roll of the dice and try to conquer Taiwan with an invasion, what if Beijing ratcheted up the kind of thing it has been doing of late—sending missiles near Taiwan when it senses that leaders in Taiwan or the United States are trying to promote Taiwan’s independence? For example, China fired a number of missiles into waters around Taiwan in August 2022 after then-Speaker of the House Nancy Pelosi visited the island. That has created a “new normal” of heightened Chinese military activity near Taiwan; next time it chooses to escalate, China could aim closer to shore. Perhaps it could take out a ship or two anchored in a port in Taiwan or destroy some shipping cranes in the harbor. Perhaps it could send 20 to 40 submarines out to sea and threaten to sink any commercial ship going in or out of Taiwan, unless that ship first docks in mainland China and allows its cargo to be inspected. Baby food and medicine might be allowed into Taiwan; anything smacking of military utility, or even high-tech goods crucial to Taiwan’s economic relationships with the rest of the world, might not be.

Beijing’s goal with this kind of limited attack might be to target Taiwan’s economy more than its people or even its military—trying to coerce, through economic pain and threatened strangulation, while limiting any loss of life. Not only would the intensity of the operation be adjustable like a rheostat, but the operation could even be temporarily scaled back if and when too many American naval ships came to Taiwan’s assistance to set up a safe shipping channel and break the blockade. Even if the United States and many core allies coalesced around the idea of a strong response (as Western nations did when the Soviets carried out the blockade of Berlin in 1948-1949), Beijing might hope that many neutral countries would overlook the relatively limited amounts of violence associated with this kind of operation and not join the U.S. coalition.

I think this is the most credible scenario. It is also, I believe, very hard for the United States to counter. We can try to sink those Chinese submarines and shoot down those Chinese missiles, but the process will be slow, and we will take losses, too. I have attempted, through simple computations, to model how these scenarios might play out. Under certain plausible assumptions, I believe the United States plus Taiwan and probably Japan would win; under other equally plausible assumptions about the performance and survivability of missiles, missile defenses, surface ships, satellites, cyber systems, and other key assets, alas, I fear China could “win” in the sense of sinking enough of our fleet needed for the counterblockade operation that we would have to call off the effort.

Of course, whichever side loses round one may try again. The loser could, for example, rearm and then simply try again in a few years, or it could expand the conflict geographically, or it could even threaten the use of nuclear weapons (like Eisenhower did during the two Taiwan crises of the 1950s). There is little reason to think this scenario could be contained and little reason to think it would end soon—even if one side or the other did seem to win at first. China would be unlikely to give up in trying to seize an island it considers rightfully its own, or to accept defeat at the hands of a country it considers its main rival. The United States, with its tradition of military assertiveness and strong devotion since the 1940s to the defense of allies, would likely see the stakes in any such war not simply as the fate of 23 million living in Taiwan, but the fate of its entire system of alliances and partnerships.

The single best way that the United States can more effectively deter a Chinese blockade of Taiwan, I believe, is to strengthen what Secretary of Defense Lloyd Austin has been calling integrated deterrence, a term I also coined in a 2019 book. It means working with allies to ensure that they too send a strong message of willingness to resist any Chinese attack—not only with military responses but also with economic preparations that would make their nations more resilient in the event of a protracted economic war pitting the United States and its allies and partners against China.

It would, of course, really be much better not to fight any of these scenarios against China! The first is quite dangerous; the second and third are profoundly perilous. Deterrence is one part of the path forward for America, but so is a commitment to crisis management—and, on some issues, even to compromise. Beijing, Taipei, and Washington all have crucial roles to play in this effort, since the irreducible objective must be to prevent a war that might not prove controllable—and that could become the greatest tragedy in the history of the human race.

By: Michael E. O’Hanlon