Strengthening Alliance With Japan Is Critical for Biden’s Indo-Pacific Strategy

During his Senate confirmation hearing, Anthony Blinken, President Biden’s nominee for Secretary of State, called for Washington “to start approaching China from a position of strength, not weakness.” Kurt Campbell, Biden’s Indo-Pacific affairs coordinator at the National Security Council, added that “a conscious effort to deter Chinese adventurism” will require U.S. support of and coordination with allies such as Japan. To that end, Washington should upgrade its defense cooperation with Tokyo in a manner that adapts to Beijing’s evolving military strategies and capabilities, in particular by deterring first strikes and enhancing U.S.-Japan interoperability.

The Defense Department’s 2019 Indo-Pacific Strategy Report appropriately called the U.S.-Japan alliance “the cornerstone of peace and prosperity in the Indo-Pacific.” Japan continues to host 54,250 U.S. troops who benefit from its critical geographic position within the first island chain between the U.S. and China. This location minimizes the time needed for the U.S. to deploy forces in response to potential conflicts throughout the Indo-Pacific.

In addition to its troops, Washington deploys a vast array of critical combat capabilities throughout Japan. For example, the islands are home to the U.S. Navy’s 7th Fleet, which currently includes the USS Ronald Reagan aircraft carrier strike group, as well as the U.S. Air Force’s 18^th Wing that includes advanced fighter jets such as the F-22 and F-35. Stationing these units in Japan brings them closer to China and other adversaries such as North Korea, reinforcing deterrence by enabling a swift U.S.-led response to potential aggression.

The Chinese leadership, however, has developed military capabilities intended to neutralize the strategic benefits that U.S. forces gain by residing in Japan. Specifically, Beijing has equipped its military, the People’s Liberation Army (PLA), with anti-access and area denial (A2/AD) capabilities such as intermediate and long-range ballistic and cruise missiles as well as new air and maritime defense systems. A2/AD’s purpose is to expel U.S. forces from potential areas of conflict. By denying the U.S. military access to the battlefield, the PLA can continue pursuing its revisionist objectives of reclaiming territories and re-drawing maritime boundaries.

Despite the necessity of maintaining a U.S. force presence in Japan, the U.S. military has planned to relocate some U.S. forces elsewhere in the region so that they are not vulnerable to the PLA’s A2/AD capabilities. The relocation also seeks to reduce the burden on certain parts of Japan that have historically hosted substantial deployments of U.S. military forces. For example, the U.S. Marine Corps announced in 2019 its plan to complete the transfer of 5,000 Marines from Japan’s Okinawa prefecture to Guam by 2024. Okinawa prefecture is the southernmost island in the Japanese archipelago.

The Marine Corps’ relocation plan is part of the broader U.S.-Japan Roadmap for Realignment Implementation of 2006. The Roadmap was intended to help reduce the burden on Okinawa, which currently hosts the majority of U.S. troops deployed in Japan, because its location enables the swiftest U.S. deployments “for the most likely U.S. military contingencies in Asia,” according to the Congressional Research Service. Specifically, Okinawa is only 500 kilometers away from China, while it is 2,000 kilometers away from Tokyo. The island’s strategic location, however, makes it very vulnerable to Chinese missile strikes – another reason for their relocation to Guam, which lies outside the range of several PLA missiles, including submarine-launched ballistic missiles, anti-ship missiles, and select cruise missile classes.

Unfortunately, relocating U.S. forces away from the Japanese archipelago would undercut U.S. deterrence in the Indo-Pacific. Moving forces away from Japan would also increase America’s response time for supporting its allies in contingency scenarios, enabling U.S. adversaries to accomplish their military objectives before U.S. reinforcements can arrive.  

The U.S. military, therefore, should not remove its forces from Japan. Instead, it should strengthen existing defenses and deploy new capabilities to bolster deterrence and to offset the growing vulnerability of bases to Chinese missile strikes and other A2/AD capabilities.

First, the U.S. should redistribute its forces across the Japanese archipelago and the first island chain rather than send them to Guam. Relocating U.S. forces and assets throughout the main Japanese archipelago would still reduce the burden on Okinawa while also boosting the survivability of U.S. troops and defense assets by moving farther away from Chinese firing range. The relocation of U.S. forces and assets would also help improve the distribution of U.S. strike power still within the critical first island chain.

For example, Washington should employ the U.S. Air Force’s Agile Combat Employment (ACE) operational concept. ACE focuses on better dispersing U.S. fighter aircraft in smaller sections across Japan by increasing the number of airbases in civilian and non-traditional areas. ACE can build more flexibility, lethality, and agility into forward-deployed units to enable their rapid dispersal throughout the island. Furthermore, the U.S. would be in a better position to prevent multiple losses in one location and to create targeting dilemmas for China so that the U.S. can establish and sustain air superiority in a conflict.

Second, the U.S. should invest in new weapons and capabilities to help deter a Chinese first strike. Specifically, the U.S. and Japan should consider deploying ground-based missiles throughout Japan that could target PLA missiles in conflict situations. This was not considered a viable option for the U.S. and Japan until August 2019, when Washington withdrew its signature from the Intermediate Nuclear Forces (INF) Treaty. The INF Treaty required the U.S. and Russia to eliminate and never use nuclear or conventional ground-launched ballistic and cruise missiles ranging from 500 to 5,500 kilometers.

Additionally, Washington and Tokyo should address vulnerabilities to ballistic missile defense architecture. Areas of reassessment should include early warning capabilities against all types of incoming missile threats as well as interception capabilities to confront these incoming strikes.

Washington should also coordinate the expansion of Japan’s anti-air capabilities in the Nansei/Ryukyu islands near the Miyako Strait, where Beijing routinely conducts maritime and air incursions. Boosting anti-air assets will help deter Chinese incursions as these deployments create a new cost for Beijing to consider before making a first move.

Third, the U.S. and Japan must boost interoperability to support a capable joint force for all conflict domains. A key area of focus should be modernizing and integrating the U.S. and Japan’s command, control, communications, computers, intelligence, surveillance, and reconnaissance (C4ISR) capabilities. Likewise, Washington and Tokyo should ensure they share a robust battlefield information network to augment the U.S. and Japan’s shared threat detection capabilities. This system will be essential to block Beijing’s efforts to attain information dominance through its own C4ISR branch, the PLA Strategic Support Force.

In sum, while the U.S.-Japan alliance has long been the cornerstone of peace and prosperity in the Indo-Pacific, there is still room for improvement. If the U.S. is serious about challenging Beijing’s persistent aggression, the Biden administration must pursue an even stronger defense partnership with Japan.

Mathew Ha is a research analyst focused on North Korea and East Asia at the Foundation for Defense of Democracies (FDD), where he also contributes to FDD’s Center on Military and Political Power (CMPP). Follow him on Twitter @MatJunsuk. FDD is a Washington, DC-based, nonpartisan research institute focusing on national security and foreign policy.