Japan: America’s indispensable ally

Over the past decade, it has become increasingly common in U.S. foreign policy circles to identify Japan as America’s “indispensable ally.” And for good reason.

From the urgent and shared need to counter-balance an increasingly assertive and powerful China to joint efforts to ensure resilient semiconductor supply chains, on a wide array of issues Japan is now widely seen as America’s most important partner in Asia, if not the world.

This trend reflects increasingly mainstream recognition of a decades-old reality: The U.S.-Japan security alliance is an essential enabler of and force multiplier for U.S. strategic objectives in the Indo-Pacific—the world’s most populous, economically dynamic, and geopolitically consequential region.

This “Election ‘24” series rightly emphasizes that “America’s approach to the world—especially its engagement with allies and partners—will have a profound impact on the rules and norms of the international system that have underpinned American security for decades and advanced global peace and prosperity.”

In 2024, no single U.S. treaty ally better illustrates this point than Japan.

Regardless of the outcomes of the U.S. November election, a robust and politically stable partnership with Tokyo will be essential for both the next administration and Congress to develop and implement a successful Asia strategy—one that builds on and moves beyond past bipartisan efforts to secure U.S. overseas interests in a peaceful and stable region, ensures continued economic prosperity at home, and realizes a “free and open Indo-Pacific.”

A unique and irreplaceable partner

As a U.S. treaty ally, Japan boasts a unique combination of strengths. To name just a few:

Japan has one of the world’s four largest economies and in recent years has been the top foreign investor in America overall and in as many as 39 of its 50 states. It boasts a mature and exceptionally stable democracy, one where supra-partisan support underpins Japan’s long-standing emphasis on the U.S.-Japan alliance as “a key pillar” of its national security policy. (For instance, 87% of the Japanese public holds positive views of America and 94% believes further developing the relationship is important for Japan and the Asia-Pacific.)

No wonder that Japan, therefore, has a long history of close foreign policy coordination with the United States. (For its part, the United States has also long benefited indirectly from Japan’s close political, economic, and—increasingly—security ties with numerous other U.S. allies and partners across Southeast Asia, Europe, and beyond.)

When it comes to geostrategic significance, Japan’s value as a U.S. treaty ally is also arguably without parallel. China, Russia, the Korean Peninsula, and the Taiwan Strait are all within 200 miles of Japanese soil, while the South China Sea—on the other side of Taiwan—is not much further. Accordingly, Japan’s continued willingness to host over 50,000 U.S. military personnel (and the U.S. Navy’s only forward-deployed aircraft carrier) is fundamental to U.S.-led efforts to deter aggression and maintain regional peace and stability.

For these and other reasons, not least of which is the U.S. military’s deepening interoperability with Japan’s highly-capable Self-Defense Forces (JSDF), the U.S.-Japan security alliance offers unique, extraordinary benefits for the United States. It serves as a potent force multiplier for U.S. foreign policy objectives in a region that successive U.S. administrations led by presidents from both major parties have defined as vital to U.S. security and prosperity.

No wonder, then, that a 2021 Government Accountability Office study commissioned by Congress identified a half-dozen benefits of the United States’ continued military presence in Japan (and Korea), including: helping maintain regional stability by deterring aggression, supporting economic prosperity, facilitating U.S. rapid response in the event of a contingency, and promoting non-proliferation.

A new era for Japan and the U.S.-Japan alliance

Although they will face an increasingly daunting and complex set of foreign policy challenges across the Indo-Pacific region, when it comes to efforts to deepen the U.S.-Japan security partnership, the next U.S. administration and 119th Congress will begin their respective terms with a strong tailwind at their backs. This is thanks in large part to a remarkable series of accomplishments under President Joe Biden and Prime Minister Fumio Kishida.

Biden and Kishida’s extensive U.S.-Japan Joint Leaders’ Statement this past April exemplifies the United States and Japan’s deepening strategic alignment as they aim to realize “a world that is free, open, connected, resilient, and secure.” Though rightly prioritizing the Indo-Pacific, the allies’ call for a “global partnership” is also a sobering reminder of the inescapable links between regional “security and stability” and developments elsewhere.

For evidence, one need look no further than Kishida’s frequent warnings that “Ukraine today may be East Asia tomorrow,” NATO’s recent judgments that North Korea is “fueling” and China is a “decisive enabler” of Moscow’s war of aggression against Ukraine, and European Union leaders’ repeated emphasis on Europe’s huge economic and other stakes in peace and stability across the Taiwan Strait.

In recent years, Japan has made historic commitments in support of the allies’ complementary strategic objectives, especially in the defense space. The past two years in particular have witnessed a striking acceleration of Tokyo’s efforts to bolster its defense capabilities, strengthen the U.S.-Japan alliance, and contribute more broadly to regional and global peace and stability—including through enhanced cooperation with U.S. Indo-Pacific and European allies.

Of particular note, under its 2022 National Security Strategy, the Kishida government pledged to “fundamentally reinforce [Japan’s] defense capabilities” with the aim, inter alia, of deterring “unilateral changes to the status quo” by China, North Korea, and others. The key enabler of this ambition is an unprecedented commitment to surge Japan’s defense budget by nearly 60% between 2022 and 2027—widely welcomed in Washington.

Perhaps no single data point better evinces the “new era” of Japan’s commitment to do more than the ~26% increase in Japan’s FY2023 defense budget, which exceeded the combined increases of the previous quarter-century in absolute terms. The Ministry of Defense’s just-released FY2025 budget request calls for even more funding to resource an ambitious slate of new investments.

Japan’s increased spending is enabling new orders for and investments in the development of new, highly advanced capabilities and platforms, an acceleration of reforms designed to improve the JSDF’s ability to operate jointly, and significant spending in long-neglected areas, including cyber and space capabilities, passive defenses, munitions, and the defense industry. This past summer, the allies also announced a historic decision to upgrade alliance coordination, command, and control.

While simultaneously bolstering its own capabilities and doubling down on the U.S.-Japan security alliance, Japan’s national security strategy also emphasizes expanded defense and industrial cooperation with third parties (read: other U.S. allies and partners). Recent examples include a historic trilateral joint statement with South Korea; reciprocal access agreements with Australia, the Philippines, and the U.K.; the launch of a 6th-generation fighter development program with the U.K. and Italy; a call to strengthen security and defense cooperation with India; and a quiet but significant expansion of multilateral exercises—including many focused on contingency response.

Leadership change on the horizon

Despite these remarkable accomplishments during the Biden-Kishida era, neither leader will still be in power come January 2025. One must hope that both sides’ future leaders will build on their predecessors’ successes in bolstering security cooperation. On this score, there is ground for (cautious) optimism.

In Japan, though it remains unclear who of the record nine candidates will replace Kishida as the Liberal Democratic Party president and therefore prime minister in a few weeks, none of the leading candidates are likely to derail the basic trajectory captured in the 2022 National Security Strategy. Notably, that strategy calls the U.S.-Japan alliance the “cornerstone” (基軸) of Japan’s security policy.

On the U.S. side, the post-presidential election trajectory is a bit more difficult to predict. A future Kamala Harris administration seems unlikely to significantly depart from the Biden-Harris administration’s approach to Asia, in particular its emphasis on the critical importance of U.S. alliances as diplomatic and military “force multipliers.”

There is far more uncertainty—and significant concern among some U.S. Asia experts—about what a second Donald Trump term might mean for the U.S. role in the world. Even so, it is worth noting that—despite turbulence on trade, host-nation support, and several other issues—during Trump’s first term, the decades-long trend of closer U.S.-Japan security cooperation basically continued.

No time to waste

Washington and Tokyo’s recent achievements mean there is much for U.S.-Japan alliance managers to celebrate. However, a vast array of sobering geopolitical trends in the Indo-Pacific and beyond makes clear that there is no time for complacency, much less a sense of “mission accomplished.”

Regardless of who wins in November, the next administration and 119th Congress can best serve U.S. national security and economic interests through a positive and comprehensive vision for the Indo-Pacific’s future; one which prioritizes long-term strategy over short-term political calculations, and results-oriented policy substance over slogans and (often cheap) “tough talk.” Increased investments in both defense and diplomacy will be critical.

And, though it seems unimaginable today given domestic political realities, U.S. policymakers should also recognize the extent to which the United States’ bipartisan abandonment of leadership on free trade and regional economic integration—both of which now move ahead largely without the United States—have undermined U.S. influence. It has also given U.S. leaders far fewer tools with which to compete effectively with China in the Indo-Pacific and beyond.

Lastly, they should also recognize the extent to which the United States’ global network of like-minded treaty allies and partners is its greatest comparative advantage in any geopolitical or strategic competition—however defined.

Among them, there is no more indispensable partner for U.S. strategic objectives in the Indo-Pacific than Japan. Regardless of who wins in November, that fundamental reality will not change.