Senate Armed Services Committee chairman Carl Levin (D–MI), ranking member John McCain (R–AZ), and Senator Jim Webb (D–VA) have called on the United States to overhaul two complex military realignment agreements with South Korea and Japan. Their proposals would undermine years of carefully crafted diplomacy that achieved U.S. strategic objectives and resolved contentious issues with allies.

The Senators’ ill-considered proposals appear to be driven more by budgetary considerations, local Guamanian constituent concerns, and Okinawan resistance than by geostrategic or security considerations. In fact, even on the cost issue—the issue closest to the Senate’s jurisdiction—their proposals would require extensive alternative construction projects, raising doubts about any claimed savings. Unilaterally delaying or abrogating the bilateral agreements would also unnecessarily strain relations with two critical allies and undermine America’s position in the Western Pacific. The U.S., South Korea, and Japan should instead maintain the current military realignment plans.

Korea Realignment Fulfills Military, Political Objectives

The current U.S. force realignment plan for Korea would make force deployments more consistent with new requirements due to increasing U.S. military capabilities. The plan also better accommodates evolving alliance roles as well as Washington’s “strategic flexibility” policy to enable U.S. forces to fulfill multiple missions.

The current plan also responds to South Korean requests that U.S. forces vacate extensive land in the center of the capital and transfer greater security responsibilities to Seoul. Both of these factors reflect a growing South Korean desire for greater sovereignty over their own defense. To halt the realignment process would affirm the perception of some in South Korea that the U.S. is an “occupying army” and risk politicizing it into a campaign issue during next year’s South Korean National Assembly and presidential elections.

The Senators question the Defense Department’s (DoD) plan to augment the number of U.S. military dependents in South Korea. Most U.S. military deployments to Korea are currently one-year, unaccompanied tours—i.e., service members are not allowed to bring their families with them. The preceding or subsequent tours are often unaccompanied tours to Afghanistan or Iraq, putting additional strains on military families, impacting troop morale and effectiveness, and reducing reenlistment rates.

The current realignment plan calls for tours to be accompanied by service members’ families. Beyond improving the military quality of life—a laudable goal—the presence of U.S. dependents is also intended to reassure South Korea of Washington’s continued commitment to defend its ally. A recurring Korean fear of abandonment by the U.S. has been exacerbated by the strategic flexibility strategy in which U.S. Forces Korea units will deploy off peninsula for training or responding to crises.

Seoul has feared that these units, without the “anchor” of dependent families, would leave South Korea permanently. This fear was realized when a reinforced brigade of the Second Infantry Division deployed from Korea to Iraq and then onward to the United States rather than returning to the Korean Peninsula. That movement reduced the overall U.S. military presence in South Korea from 37,000 to 28,500.

Japan Agreement Is a Delicate Compromise

Levin, McCain, and Webb advocate examining the feasibility of integrating helicopter units from the Futenma Marine Corps Air Station into the U.S. Air Force’s Kadena Air Base, both on Okinawa. But this option has already been repeatedly assessed and rejected by both Japan and the United States.

In 2009, the Democratic Party of Japan (DPJ) campaigned on an initial promise to remove the U.S. Marine Corps air units from Okinawa. After entering office, senior DPJ policymakers realized that the Marines are an indispensable and irreplaceable element of any U.S. response to an Asian crisis. The DPJ also pursued the Kadena integration option in 2009–2010 but rejected it after learning that it is infeasible.

Insufficient Capacity at Kadena for Integration

The Kadena Air Base is in a densely populated area, which precludes expansion. Despite its immense size, Kadena does not have sufficient capacity to incorporate Futenma air operations.

Kadena’s aircraft storage capacity is already maxed out from housing F-15 fighters, P-3 maritime patrol aircraft, MC-130 special operations transport aircraft, KC-135 aerial refueling tankers, E-3 AWACS, RC-135 reconnaissance aircraft, and HH-60 search and rescue helicopters. These planes provide combat support; intelligence, surveillance, and reconnaissance; aerial refueling; transport; special forces capabilities; search and rescue; and airborne command and control capabilities—all deemed to be critical requirements.

Integrating Marine helicopter operations into Kadena would double daily flight operations, significantly increasing safety and noise concerns and degrading an already difficult operational and training environment. In addition, consolidated Futenma and Kadena flight operations would exceed existing Kadena runway and ramp maximum-on-ground storage capabilities for surge operations during a military crisis or humanitarian emergency.

Redeploying to Guam Would Weaken Alliance Capabilities

The Senators casually suggest that U.S. Air Force units now at Kadena could be dispersed “into other areas of the Pacific region.” They fail to understand that all of the units are on Okinawa to fulfill critical treaty commitments and other alliance missions and are already best positioned to deal with the highest probability contingencies.

Okinawa’s strategic location contributes to potent U.S. deterrent and power projection capabilities and enables rapid and flexible contingency response. Redeploying U.S. forces from Okinawa to Guam would reduce these capabilities. Guam is 1,400 miles, a three-hour flight, and multiple refueling operations farther from potential conflict zones in and around Japan and Korea. Some of the planes currently at Kadena do not have aerial refueling capability, reducing their availability and effectiveness if redeployed to Guam.

Moving fixed-wing aircraft to Guam would drastically reduce the number of combat aircraft and logistic sorties that U.S. forces could conduct during crises involving North Korea or China while exponentially increasing and likely exceeding refueling and logistic capabilities. Deploying additional aircraft carriers would not be sufficient. Aircraft carriers cannot support transport or air-to-air refueling aircraft, nor can they generate the necessary combat aircraft sorties planned for both Kadena and Futenma during contingency and combat operations.

Potentially Dangerous

If Levin, McCain, and Webb have concerns about the slow pace of DoD planning and construction or doubts over the manner in which military realignment funds have been dispersed, then they should address those specific issues. But advocating that comprehensive U.S. military realignment plans in two countries be brought to a screeching halt is counterproductive at best and strategically dangerous at worst.

Accepting the Senators’ recommendations would push U.S. Air Force and Marine Corps units away from potential conflict zones. Diminishing U.S. military assets would concern the nation’s Asian allies, degrade American deterrent and defense capabilities, embolden North Korea and China, and signal a U.S. retreat from Asia.

Bruce Klingner is Senior Research Fellow for Northeast Asia in the Asian Studies Center at The Heritage Foundation.