Hal Brands
Hal Brands is the Henry A. Kissinger Distinguished Professor at the Henry A. Kissinger Center for Global Affairs at Johns Hopkins University's School of Advanced International Studies and a senior fellow at the Center for Strategic and Budgetary Assessments. His latest book is "American Grand Strategy in the Age of Trump."

Why Japan is Gearing Up for Possible War with China

If China were to attack Taiwan, it wouldn’t just have to face a hostile superpower. It would also likely have to confront its longstanding regional rival, Japan. For centuries, Japan and China have vied for hegemony in East Asia; at times, they have threatened each other’s survival. Today, as I found from three days of meetings with Japanese officials and analysts in Tokyo, the threat of Chinese aggression is producing a quiet revolution in Japanese statecraft — and pushing the nation to get ready for a fight.

For the US, China is a dangerous but distant challenge. For Japan, China is the existential danger next door. Years before American leaders were proclaiming the return of great-power rivalry, Japanese officials were warning that Beijing was up to no good. As China’s capabilities become more formidable and its conduct in the Taiwan Strait more menacing, Tokyo’s concerns grew more acute.

The weather may have been beautiful when I visited the capital, but there is very much a sense that storms are on the horizon. “Ukraine today may be East Asia tomorrow,” warned Prime Minister Fumio Kishida in June. The same month, some 90% of the Japanese public believed the country should prepare for a Chinese invasion of Taiwan. That was before Chinese leader Xi Jinping ratcheted tensions by firing ballistic missiles into Japan’s exclusive economic zone following House Speaker Nancy Pelosi’s visit to Taipei.

In Tokyo, as in Washington, opinions differ regarding when the risk of war will be greatest, and even whether Xi would hazard everything in a high-stakes military gamble. Some officials told me that Xi’s recent personnel reforms — which included placing a veteran of China’s last foreign conflict, against Vietnam in 1979, and a former commander of Chinese military forces opposite Taiwan in the two top spots on the Central Military Commission — amount to a creation of a “war council.” Others counter that the People’s Liberation Army will lack key capabilities necessary to invade Taiwan, such as sufficient amphibious landing craft, for years to come.

But there is little debate the country must brace for trouble, because China taking Taiwan by force would be disastrous for Japan.

If Taiwan fell, the islands at the far southwestern end of the Japanese archipelago might become indefensible. China could constrict Japan’s vital trade routes, increase the pressure around the disputed Senkaku Islands, and otherwise coerce its historic rival.

This is why the Tokyo government has stated — as strongly as it can, given Japan’s post-1945 aversion to the use of force — that it would not stand by while Taiwan was subjugated. Already a serious regional military power, Japan is moving rapidly to strengthen its capabilities for deterrence and defense.

Japan plans to nearly double defense spending by 2027. It is turning some of the southwestern islands into strongpoints studded with anti-ship missiles and air defenses; it reportedly has plans to use its high-quality submarine fleet to bottle up the Chinese navy. Tokyo is also moving to acquire American Tomahawk cruise missiles and other “counterstrike” capabilities that could target the Chinese mainland.

Some of these moves are publicly justified as measures to deal with a very real threat from North Korea, which livened my arrival in Tokyo by launching ballistic missiles that triggered alerts for residents of north and central Japan to seek cover. But Japanese officials acknowledged privately to me that every crisis with Pyongyang strengthens their argument for acquiring weapons that can blunt aggression by Beijing.

Meanwhile, cooperation with the US is getting deeper, with American and Japanese forces stepping up training together – including large-scale exercises off several southern islands this month – and preparing joint-operational plans in case conflict over Taiwan breaks out.

These measures are part of a larger shift, as Tokyo — which in the 1930s and 40s ravaged its neighbors — becomes a pillar of Indo-Pacific security. When the US withdrew from the Trans-Pacific Partnership trade agreement under President Donald Trump, Japan salvaged a pared-down version of that accord, to act as a counterweight to Chinese influence.

Japanese officials are weaving a web of security partnerships, with countries from Australia to India, meant to strengthen checks against Chinese expansion. Tokyo even coined the idea of preserving a “free and open Indo-Pacific,” a phrase Washington has now appropriated.

To be sure, it’s a halfway revolution. Doubling defense spending would take Japan’s military outlays to just 2% of GDP. The country’s constitution still imposes serious constraints on foreign and defense policy. But the overall trend is clear and, most likely, durable. Kishida, once considered a dove, is carrying out the policies that his more hawkish predecessor, Shinzo Abe, envisioned — without provoking nearly as much blowback as the more polarizing Abe.

This is good news for Washington. Access to Japanese bases and the involvement of Japanese forces would make the odds in a war over Taiwan far more favorable for the US. An alliance that began as a one-way security guarantee after World War II is steadily evolving into a more authentic partnership.

That’s not say that the two countries are in lockstep. The volatility of US politics and the legacy of the Trump years have led to lingering concerns about America’s long-term reliability. As I learned in Tokyo, Japanese think-tanks are quietly studying geopolitical “plan B’s” (or “plan A’s”) in case Trump returns to power. Military and diplomatic investments that make Japan a better ally of the US today serve as insurance against a future in which America retreats into isolationism or angry unilateralism.

Japanese and American diplomats I spoke to also worried that Washington sometimes elevates the symbolic aspects of support for Taiwan, such as the Pelosi visit or calls to recognize that island as an independent country, over concrete action to strengthen its defenses. Whereas Tokyo prefers deterrence without provocation, the US periodically practices provocation without deterrence. That’s not a good way to handle a dangerous rival — or to keep America’s single most crucial ally in the fold.