The Military Side of Strategic Rebalancing

The Asia-Pacific is emerging as the world's most militarily significant and challenging region. China's military has benefited from decades of double-digit growth in investment and today represents a robust fighting force focused, in part, on denying the United States access to the western Pacific during a time of crisis or conflict. North Korea continues to threaten the peace and stability of the entire region, and has not shown an interest in abandoning belligerence and confrontation since the death of Kim Jong-il. Seveal U.S. allies in Asia—Japan, the Republic of Korea (ROK), and Australia—have built highly capable armed forces that are (to varying degrees) well integrated with U.S. forces. At the same time, other regional partners and new potential partners—Singapore, India, Indonesia, and Vietnam—have also been increasing their investments in military capabilities in recent years.

For decades, U.S. military leadership and dominance has preserved the stability of the Asia-Pacific, sustained open and stable global commons, and enabled a remarkable period of regional economic development and integration.¹ Freedom of navigation has been an essential aspect of U.S. foreign policy and military strategy since the early years of the republic, when the United States fought two wars against the Barbary pirates and another against Great Britain, in part, to defend U.S. access to the high seas. As new technologies have given humanity access to the global commons, the same principles of freedom of navigation have been expanded to include all global commons.

The Asia-Pacific's increasing significance to U.S. security, prosperity, and interests—combined with a changing balance of military power—demands significant attention by American strategists and policymakers. As the wars in Iraq and Afghanistan draw to a close, and as military challenges in the Asia-Pacific continue to emerge, shifts in the United States' military posture and force structure should be expected. Strategic rebalancing is thus a natural outgrowth of a changing strategic environment.

The military aspects of strategic rebalancing should be understood to include two interconnected efforts: geographic rebalancing and capability rebalancing. Geographically, strategic rebalancing involves adjustments to the United States' long-standing regional strategy, military posture, and force structure to account for emerging challenges and opportunities. In terms of military capabilities, strategic rebalancing involves investments in hardware, systems, and technologies necessary to sustain a force structure that can defend the security and interests of the United States and its allies in the face of rapidly emerging regional military challenges.

Geographic Rebalancing

The United States has sustained a military presence in the Asia-Pacific since Commodore Matthew Perry's 1852-54 expedition to Japan. The intervening 160 years have seen the United States gain possession of Hawaii and Guam; fight wars against Japan, on the Korean Peninsula, and in Vietnam; and sustain a network of alliances in the region throughout the Cold War and since. Although the Defense Policy Review Initiative (DPRI) is often discussed in terms of the U.S. Marine Corps' footprint in Okinawa, it was actually one product of an extensive Asia-Pacific force posture and footprint review conducted by U.S. Pacific Command and approved by the secretary of defense in 2004. The DPRI included additional initiatives to move part of the navy's air wing in Japan from Atsugi to Iwakuni to deal with encroachment issues, effectively removing a brigade from Korea and gaining agreement to adjust U.S.-ROK command relationships. Additional, smaller adjustments were made to the army, air force, and special forces of Pacific Command to improve interaction and interoperability with key partners and to start the process of putting a greater emphasis on Southeast Asia. Three submarines were moved to a homeport in Guam in this same period to increase U.S. operating tempo and ability to respond rapidly to crisis. As of 2011, the United States officially had over 83,000 active-duty troops stationed in East Asia and the Pacific, with most in Japan (39,222), the ROK (28,500), and at sea (15,599).²

The coming years will likely see a modest shift in...