With this week’s news that the United States has finally reached an agreement to cut the number of Marines stationed on the Japanese island of Okinawa, an ongoing standoff in the South China Sea between a Philippine Coast Guard cutter and a Chinese ocean surveillance ship, which is now in its third week, has taken on added significance.

The incident began in early April when the crew of a small Philippines warship attempted to arrest some Chinese men for illegal fishing near the disputed Scarborough Shoal, 124 miles northwest of Luzon. China quickly dispatched two surveillance ships and blocked the arrest of the men, who slipped away. China later recalled one its ships and Manila replaced its warship with the cutter, which defused the crisis a bit. In Beijing, the Philippine charge d’affaires has twice been summoned to the foreign ministry to receive lectures on why the rocks under dispute fall within China’s “inherent territory.”

With this as a backdrop, “Balikatan 2012,” a 10-day US-Philippine military training exercise, began on April 16. The 28th annual iteration of the exercise this year included a variety of manoeuvres, including a simulated capture of an island by Philippine and US Marines, staged in daylight for a large media contingent on Palawan Island, facing the South China Sea. Besides US and Philippine military forces, Balikatan 2012 also included a command post exercise conducted with representatives from the Association of Southeast Asian Nations (ASEAN). Philippine President Benigno Aquino used the flurry created by these events to warn his country’s neighbours over China’s ‘aggressiveness’ in the South China Sea. “They claim this entire body of water practically. Look at what is excluded and what they are claiming,” Aquino told reporters as he pointed to a map of the area. “So how can the others not be fearful of what is transpiring?” After the military exercises wrap up, Aquino’s foreign minister will be off to Washington for consultations with US officials.

If Aquino and his ASEAN colleagues are to have the confidence to stand up to China, few would dispute that they will require diplomatic support from the United States. Indeed, in 2010, when several members openly pushed back against Beijing at two ASEAN Regional Forum meetings in Hanoi, US Secretary of State Hillary Clinton and then Secretary of Defence Robert Gates were there to back them up. Since then, Southeast Asian leaders who are attempting to handle China’s assertions seem to have warmed up to the idea of a more visible US military presence in the area. For the South China Sea, that would mean a US Navy and Marine presence to support Washington’s partners in ASEAN. The challenge for all of these players is how to arrange this supporting presence so that it is credible yet also politically sustainable.

Unfortunately, the Pentagon has still not figured out where it will base its Marine Corps units in the Pacific. A work-in-progress since the 1990s, version after version of Marine basing plans have gone down in flames, including a 2010 debacle that took down the prime minister of Japan.

US partners around the South China Sea want a stabilizing US presence, something Washington wants to provide. But the Pentagon won’t be able to show exactly how it will support that mission until it finally determines where it is going to actually put its Marines.

Planners now agree that the Marine presence on Okinawa will shrink. The 2006 version of the plan would have transferred 8,600 Marines and 9,000 dependents about 1,500 miles southeast to Guam, a move that would have required $21.1 billion in construction costs to complete. The Marine Corps presence on Okinawa has become too politically toxic for the Japanese government. In addition, some military analysts fear that in a shooting war with China, missile strikes could close US air bases and ports on the island, preventing the Marine infantrymen there from getting to where they might be needed. Meanwhile, the bill for the huge buildup on Guam came in much too high and would have concentrated too many assets on one spot. Last year, Senators Carl Levin, John McCain, and James Webb objected to the Guam plan and demanded a rewrite.

The latest plan scales back the Guam move to 4,700 Marines with 2,700 more moving to existing bases in Hawaii. That will reduce the Pentagon’s Guam construction bill. However, Levin, McCain, and Webb still want to know how the latest basing proposal, “relates to the broader strategic concept of operations in the region.”

Providing a forward presence in places like the South China Sea and reacting to military and humanitarian crises will be the major missions for the Marine Corps in the Pacific. How best to position Marine units to accomplish these tasks remains unsettled.

Aquino seems to welcome a stepped-up US military profile in his neighbourhood. But that doesn’t mean he wants a return to the large and politically overbearing bases the United States operated in the Philippines until 1992, when a political consensus in the country threw the US forces out. It is likely that a majority on Okinawa would follow suit, if they had the authority to do so.

The political path of least resistance will be to relocate overseas units back to bases in the United States (something almost all congressmen will welcome) and then fly or sail these units back out on relatively short-term deployments and training exercises in partner countries. Darwin, Australia, is already preparing to eventually host up to 2,500 Marines on six-month rotational deployments. The Philippines may soon roll out a similar welcome mat. Other countries in the region may follow.

In addition to reducing the corrosiveness of large foreign bases such as those in Okinawa and formerly in the Philippines, the rotational deployment method has other benefits. It will condition US military forces and planners to an expeditionary mind-set. Logisticians will further improve their already formidable skills at moving military units around the world, skills that will always be handy during crises. Military units will learn to become more nimble, adaptable, and flexible, increasing their usefulness during crises. With deployments as the standard model, US military personnel will become acquainted with a wider variety of foreign partners than they would under a static basing scheme. And when units are not deployed, they will be back at bases in the United States, which will have better training facilities and better family accommodations than those overseas.

The deployment approach has its risks. US naval and air forces face increasing challenges from long-range, anti-ship, and anti-aircraft missiles. The ability of some adversaries to use these missiles to impose “anti-access, area denial” measures against the movement of US reinforcements into crisis areas would be especially troubling for the deployment model. From a diplomatic perspective, some will question whether a US strategy that relies more on distant deployments and less on a permanent forward troop presence will be sufficiently reassuring to partners who might be ‘under stress’ from a strong nearby neighbour like China.

Under a growing missile threat, field commanders will likely prefer the flexibility afforded by an expeditionary approach compared to the vulnerability of fixed bases - such as Okinawa - located within easy range of Chinese missiles. The new slimmed-down relocation plan to Guam will still cost an estimated $8.6 billion, spent on elaborate barracks, family housing, and training ranges. Instead of building up another increasing vulnerable fixed base, the Pentagon should consider using that money to acquire additional Marine amphibious ships and anti-missile destroyers to protect them. That would boost forward presence and flexibility, which should be reassuring to both alliance partners and US commanders in the region.

         –Foreign Policy