When I first visited Japan more than 30 years ago, the Cold War had ended, China had not yet risen, and the country—although it was no longer the Japan as Number One of Ezra Vogel’s best-selling 1979 book—was formidable. Japan’s GDP was not very far behind that of the United States, was larger than that of most of the rest of Asia combined, and was seven times that of China.On a recent visit, I found a very different country. Even in 1995, there were ominous signs: the collapse of property prices and several years—which would stretch into decades—of economic stagnation. Birth rates were below replacement, at roughly 1.4 per woman, although they have since fallen further, to a bit more than 1.1. But some of the biggest changes lie in Japan’s geopolitical environment.Today, Japan’s GDP is roughly a fifth of China’s, and although the size of its armed forces remains roughly the same as in the past, it is now far outstripped by that of its continental neighbor. Back in 1995, North Korea was still a decade away from testing a nuclear weapon; today, it has dozens or even scores of weapons that it can deliver. And back then, Russia was still recovering from its rocky transition out of Communist rule; today, it is aligned with China and routinely provides military technology to China and North Korea.Small wonder that the Japanese political, military, and intelligence leaders as well as academic experts I recently spoke with were grim. They cling to their security treaty with the United States, but their government is also doing once-unthinkable things to ensure their own defense.[Michael Schuman: China is flatlining]For most of the postwar period, Japan relied on its defense treaty with the Americans and on robust economic growth. Defense spending was held at 1 percent of GDP, but its economy was so much larger than those of its neighbors that this meant a relatively substantial investment in the Japan Self-Defense Forces. Despite its love of samurai movies and martial arts, Japan remained a pacifist country that did not export weapons, focused on defensive missions, and pledged not to produce, possess, or host nuclear weapons.All of that has changed. Under plans adopted in 2022, Japan has increased its defense spending to something like 1.4 percent of GDP, and Prime Minister Sanae Takaichi has indicated that it will rise to 2 percent. It is likely to go beyond that, possibly even as far as the 3.5 percent target now generally accepted in Europe. The result is not just an improvement of Japanese weapons systems across the board (numbers of service personnel remaining stable), but the acquisition of new capabilities. Japan is now openly acquiring what it calls “counterstrike” weapons—that is, missiles of various kinds that can hit targets on the Chinese mainland. It is investing in cyber and space operations, as well as in much greater air and missile defenses. It is building concrete shelters and digging tunnels for passive defense against Chinese attacks on its bases, something that the United States has inexplicably failed to do in either Asia or the Middle East. Japan is newly willing to sustain its defense industries by exporting weapons. This year it created its first centralized intelligence agency—the National Intelligence Bureau—since World War II.Most interesting of all is the shift in Japanese attitudes to nuclear weapons. The Japanese policy toward those weapons after World War II was grounded in the trauma of being the only country to have suffered a nuclear attack. On this trip, I heard nary a word about Hiroshima or Nagasaki, but a great deal about deterrence.More to the point, Japanese officials and experts were virtually unanimous on the need to drop at least one of the three legs of its nuclear policy: the prohibition of introducing nuclear weapons on Japanese soil. They were eager to explore the possibility of arrangements with the United States comparable to those with Germany or other European countries, under which both countries have their finger on the nuclear button, a so-called dual key. A submarine-launched cruise missile with a nuclear warhead, now under development in the U.S., seems to be the preferred system.Japan could easily develop nuclear weapons. It has ample supplies of plutonium and outstanding engineers. It would much prefer not to, for a host of reasons, including lingering domestic opposition and fear of preemptive attack. But the arguments I heard against a purely Japanese nuclear deterrent are now cast in prudential terms, not emotional or historical ones.These changes emerge from a heightened Japanese sense of threat. Almost every day, Chinese coast-guard vessels enter the contiguous zone (12 to 24 miles out) around the Senkaku Islands, which stretch almost to Taiwan, and they commonly intrude into Japanese territorial waters there. The Chinese coast guard, it should be noted, has vessels the size of frigates or destroyers in other navies, and that have mounted automatic cannons of the type used for combat rather than law enforcement. Their belligerent rhetoric upon encountering their Japanese counterparts matches that of their government.Joint Chinese and Russian air patrols unnerve Japan’s air defenders, as do increasing flights of Chinese drones near Japanese islands. China’s insistence that the Senkaku Islands are Chinese is of long standing but has become more strident in recent years. Meanwhile, Japan looks with dismay at a China whose nuclear arsenal is growing quickly, as is that of North Korea. And both are aligned with a Russia whose navy and air force remain active in the Pacific despite the demands of the fighting in Ukraine.[From the January 2026 issue: The new German war machine]Japan is in a tough spot, and for that and other reasons, its attitude to the United States is different from that of many European countries. In Japan, one seldom hears complaints about democratic backsliding or accusations of betrayal. Rather, the Japanese are desperate to put their faith in the U.S. at a time when alternatives are few.There is no Pacific NATO, and even the combined command of U.S. and Japanese forces is not nearly as organizationally robust as that of the United States and South Korea. There is only the presence of American forces (oriented for the most part toward Korea and Taiwan) and America’s good word, as well as Japan’s determination to resist encroachment—or, as its defense documents call it, “invasion”—by a hostile China.Japan’s anxieties around Taiwan are high. Even a peaceful takeover of the island by China would represent a major setback. It would unhinge Japan’s and the United States’ strategic posture in East Asia, and encourage (in Japan’s view) accommodation or worse from some of China’s neighbors. In a seemingly spontaneous remark in late 2025, Prime Minister Takaichi indicated that a Chinese naval blockade of Taiwan would count as a “survival-threatening situation” that would, by implication, permit Japan’s use of force for collective self-defense. Despite the furor that erupted, she has not withdrawn those remarks.The next few years may be perilous in East Asia if China sees an opportunity created by a distracted and underequipped America to accomplish its goal of unifying an unwilling Taiwan with the mainland. Thankfully, the U.S.-Japan relationship is an alliance that the Trump administration has not yet heedlessly and willfully damaged. For the sake not only of Tokyo, but of peace in the region, one hopes that will remain the case.