Japan, a country constitutionally bound to pacifism since World War II, is investing in its defense and contributing to regional security in ways that were previously unthinkable. Tokyo has nearly doubled its defense budget, purchased long-range missiles capable of striking military targets in China and North Korea, signed agreements that allow it to deploy its military overseas, stepped into combat roles in multilateral military exercises, and even lifted its prohibition on exporting weapons.

Japan’s current strategy benefits the United States. Tokyo is not moving away from its alliance with Washington or seeking strategic autonomy; instead, it is increasing the durability of U.S. power in the Indo-Pacific. The United States should be helping accelerate these reforms because a stronger Japan that is closely linked with other U.S. allies and partners in the region is essential to deterring a highly capable and assertive China. Japan is offering the United States a way to protect its vital interests in the Indo-Pacific at a much lower cost and with less risk than Washington would otherwise have to bear.

The United States, however, risks squandering this opportunity by not prioritizing its relationship with Japan. In November 2025, Japanese Prime Minister Sanae Takaichi made comments about defending Taiwan that led Beijing to launch a massive coercion campaign against Tokyo, including throttling its supply of heavy rare-earth minerals and suspending Japanese seafood imports. Despite Takaichi’s statements being in line with U.S. policy preferences, Washington chose not to forcefully stand up for her in public. Then, in May 2026, Washington informed Tokyo that because of the war in Iran, it was delaying the delivery of Tomahawk missiles that Japan had purchased more than two years earlier, and in August, Washington temporarily moved the only aircraft carrier permanently deployed outside the United States from East Asia to the Middle East.

For now, Japan has looked past these developments and is still investing in its partnership with the United States. It does not have any better alternatives to Washington. But the U.S.-Japanese alliance will not automatically endure forever, and the current U.S. approach could soon drive Japan to lower its ambitions for the alliance. The U.S.-Japanese relationship is nearing an inflection point, where complacency in Washington about the alliance and dismissiveness toward Tokyo could leave the United States with less power and influence across the Indo-Pacific. The United States needs to visibly demonstrate its desire for a more ambitious U.S.-Japanese alliance and expand economic and military collaboration with Japan before it’s too late.

For decades, the U.S.-Japanese alliance rested on a division of labor: the United States guaranteed Japan’s security and Japan channeled its national energy into economic reconstruction. This bargain, although asymmetric, satisfied both parties. The United States got a secure regional presence to contain Soviet power in Asia during the Cold War while also preventing a revival of Japanese militarism, and Japan obtained the security it needed to rebuild its shattered economy.

But a cascade of external shocks in the past two decades forced Japanese leaders to revisit this postwar bargain. In 2010, when tensions flared over the disputed Senkaku Islands (known in China as the Diaoyu Islands), Beijing imposed an informal embargo on rare-earth mineral exports to Tokyo, showing its willingness to weaponize supply chains and highlighting Japan's vulnerability to coercion. After U.S. President Barack Obama declared Syria’s use of chemical weapons to be a “redline” but did not enforce it, and as Washington did little to halt China’s militarization of islands and shoals in the South China Sea, Japan started to question the credibility of U.S. commitments. Russia’s invasion of Ukraine, in 2022, further demonstrated that great powers were willing to use force to redraw territorial borders. And in the wake of U.S. Speaker of the House Nancy Pelosi’s visit to Taiwan that same year, China’s aggressive live-fire military exercises made clear to Japan that a cross-strait conflict was no........

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