In the U.S. military, at least, the “pivot” to Asia has begun. By 2020, the navy and the air force plan to base 60 percent of their forces in the Asia-Pacific region. The Pentagon, meanwhile, is investing a growing share of its shrinking resources in new long-range bombers and nuclear-powered submarines designed to operate in high-threat environments.

These changes are clearly meant to check an increasingly assertive China. And with good reason: Beijing’s expanding territorial claims threaten virtually every country along what is commonly known as “the first island chain,” encompassing parts of Japan, the Philippines, and Taiwan—all of which Washington is obligated to protect. But to reliably deter Chinese aggression, the Pentagon will have to go even further. Emerging Chinese capabilities are intended to blunt Washington’s ability to provide military support to its allies and partners. Although deterrence through the prospect of punishment, in the form of air strikes and naval blockades, has a role to play in discouraging Chinese adventurism, Washington’s goal, and that of its allies and partners, should be to achieve deterrence through denial—to convince Beijing that it simply cannot achieve its objectives with force.

Leveraging the latent potential of U.S., allied, and partner ground forces, Washington can best achieve this objective by establishing a series of linked defenses along the first island chain—an “Archipelagic Defense”—and, in so doing, deny Beijing the ability to achieve its revisionist aims through aggression or coercion.

THE RISKS OF REVISIONISM

China claims that its rise is intended to be peaceful, but its actions tell a different story: that of a revisionist power seeking to dominate the western Pacific. Beijing has claimed sovereignty over not only Taiwan but also Japan’s Senkaku Islands (known in China as the Diaoyu Islands) and most of the 1.7 million square miles that make up the East China and South China Seas, where six other countries maintain various territorial and maritime claims. And it has been unapologetic about pursuing those goals. In 2010, for example, China’s then foreign minister, Yang Jiechi, dismissed concerns over Beijing’s expansionism in a single breath, saying, “China is a big country, and other countries are small countries, and that is just a fact.”

Consider Beijing’s recent bullying in the South China Sea. In March 2014, Chinese coast guard boats blocked the Philippines from accessing its outposts on the Spratly Islands. Two months later, China moved an oil rig into Vietnam’s exclusive economic zone, clashing with Vietnamese fishing boats. The moves echoed earlier incidents in the East China Sea. In September 2010, as punishment for detaining a Chinese fishing boat captain who had rammed two Japanese coast guard vessels, China temporarily cut off its exports to Japan of rare-earth elements, which are essential for manufacturing cell phones and computers. And in November 2013, China unilaterally declared an “air defense identification zone,” subject to its own air traffic regulations, over the disputed Senkaku Islands and other areas of the East China Sea, warning that it would take military action against aircraft that refused to comply.

Some have suggested that as its military grows stronger and its leaders feel more secure, China will moderate such behavior. But the opposite seems far more likely. Indeed, Beijing’s provocations have coincided with the dramatic growth of its military muscle. China is now investing in a number of new capabilities that pose a direct challenge to regional stability. For example, China’s People’s Liberation Army is bolstering its so-called anti-access/area-denial capabilities, which aim to prevent other militaries from occupying or crossing vast stretches of territory, with the express goal of making the western Pacific a no-go zone for the U.S. military. That includes developing the means to target the Pentagon’s command-and-control systems, which rely heavily on satellites and the Internet to coordinate operations and logistics. The PLA has made substantial progress on this front in recent years, testing an antisatellite missile, using lasers to blind U.S. satellites, and waging sophisticated cyberattacks on U.S. defense networks.

China is also enhancing its capacity to target critical U.S. military assets and limit the U.S. Navy’s ability to maneuver in international waters. The PLA already has conventional ballistic and cruise missiles that can strike major U.S. facilities in the region, such as the Kadena Air Base, in Okinawa, Japan, and is developing stealth combat aircraft capable of striking many targets along the first island chain. To detect and target naval vessels at greater distances, the PLA has deployed powerful radars and reconnaissance satellites, along with unmanned aerial vehicles that can conduct long-range scouting missions. And to stalk U.S. aircraft carriers, as well as the surface warships that protect them, the Chinese navy is acquiring submarines armed with advanced torpedoes and high-speed cruise missiles designed to strike ships at long distances.

Beijing’s actions cannot be explained away as a response to a U.S. arms buildup. For the last decade, Washington has focused its energy and resources primarily on supporting its ground troops in Afghanistan and Iraq. The U.S. defense budget, which until recently stood at above four percent of the country’s GDP, is projected to decline to less than three percent by the end of the decade. Simply put, the Pentagon is shedding military capabilities while the PLA is amassing them.

Yet if the past is prologue, China will not seek to resolve its expansionist aims through overt aggression. Consistent with its strategic culture, it wants to slowly but inexorably shift the regional military balance in its favor, leaving the rest of the region with little choice but to submit to Chinese coercion. For the most part, China’s maritime neighbors are convinced that diplomatic and economic engagement will do little to alter this basic fact. Several of them, including Japan, the Philippines, and Vietnam, are increasingly focusing their militaries on the task of resisting Chinese ambitions. They know full well, however, that individual action will be insufficient to prevent Beijing from carrying its vision forward. Only with U.S. material support can they form a collective front that deters China from acts of aggression or coercion.

DETERRENCE THROUGH DENIAL

If Washington wants to change Beijing’s calculus, it must deny China the ability to control the air and the sea around the first island chain, since the PLA would have to dominate both arenas to isolate the archipelago. The United States must also integrate allied battle networks and strengthen allied capabilities—both of which will help offset the PLA’s efforts to destabilize the region’s military balance. By and large, those goals can be achieved with ground forces, which would not replace existing air and naval forces but complement them.

When it comes to air defenses, states along the first island chain could buttress their ability to deny China access to airspace by employing army units equipped with highly mobile and relatively simple short-range interceptor missiles (such as the Evolved Sea Sparrow, supported by GIRAFFE radar systems to detect targets). The U.S. Army, meanwhile, along with such allies as Japan, could operate more sophisticated, longer-range systems capable of intercepting Chinese cruise missiles and destroying advanced Chinese aircraft. Although not part of the first island chain, Vietnam is already enhancing its air-denial capabilities and could contribute to a larger defense effort.

Then there is the task of denying the PLA the sea control it would need to mount offensive operations against the islands. Senior members of Congress have encouraged the U.S. Army to consider resurrecting an artillery force for coastal defense, a mission it abandoned after World War II. The idea is simple and compelling. Rather than risk sending warships within range of PLA defenses or diverting submarines from higher-priority missions, the United States and its allies could rely on ground forces, based along the first island chain and armed with mobile launchers and antiship cruise missiles, to perform the same operations. Japan’s military has done exactly that, placing shore-based antiship cruise missile units on some of the Ryukyu Islands during military exercises. Vietnam has fielded similar systems. And other frontline states could follow suit, either independently or with U.S. funding, training, and technical assistance.

Another mission to which U.S. and allied ground forces could contribute is naval mine warfare. Traditionally, naval ships lay and clear mines to restrict or allow transit through narrow seas and straits. Although clearing mines will remain an inherently naval function, ground forces could play a larger role in laying them, particularly if stationed near the key straits that link the East China and South China Seas to the open oceans. Armed with the ability to emplace sea mines from land bases using short-range rockets, helicopters, or barges, U.S. and allied ground forces could make large stretches of sea off-limits to the Chinese navy. Minefields at key chokepoints along the first island chain would greatly complicate a Chinese naval offensive and hamper China’s ability to harass allied naval forces. Nearby coastal antiship missile batteries, meanwhile, could make mine-clearing operations risky for PLA ships.

Over the long run, ground forces could also support operations against the PLA’s growing submarine force. A submarine relies heavily on its stealth for defense; once noticed, it must evade contact or assume a high risk of destruction. By placing low-frequency and acoustic sensors in the water around the first island chain, U.S. and allied forces could augment their ability to detect the presence of PLA submarines. Coastal artillery units could then use rocket-launched torpedoes to induce oncoming submarines to abandon their missions and retreat.

If China invaded a U.S. ally or partner, even a small number of U.S. ground troops could help local forces mount a determined resistance. Modern conflicts in Southeast Asia and the Middle East have demonstrated what a modest irregular ground force can achieve with the help of modern weapons and capable advisers. Thanks to U.S. advisers and airpower, an overmatched South Vietnamese army was able to withstand a full-scale assault by North Vietnamese forces in 1972. Nearly three decades later, in 2001, a small contingent of U.S. Special Forces, backed by strike aircraft, helped Afghanistan’s Northern Alliance defeat the Taliban. And in 2006, Hezbollah fighters in Lebanon, with the assistance of Iranian advisers, fought the Israeli Defense Forces to a standstill for a month. A similar effort by U.S. ground forces in the Pacific could make seizing and occupying territory an extremely costly proposition for China, especially if local forces also had advanced training and equipment. Access to short-range, precision-guided mortars, rockets, and shoulder-fired antiaircraft missiles, for example, would maximize the lethality of small guerrilla resistance units.

By shouldering greater responsibility for denying the PLA the air and sea control it needs to mount offensive operations, ground forces could liberate U.S. and allied air and naval forces to perform the missions only they can accomplish, such as long-range surveillance and air strikes. Should deterrence fail, these air and naval assets would prove critical to defending the first island chain and offsetting PLA advantages. For example, the PLA can concentrate forces at any point along the first island chain far more rapidly than can the United States and its allies, whose militaries are more widely distributed. And it doesn’t have to reconcile conflicting national interests. (In the wake of a Chinese offensive against a single island, countries along the chain would likely want to keep their forces in place to defend their homelands.) By reducing the demands on U.S. air and naval forces for such missions as air and sea denial, ground forces would enable these air and naval forces to stand in reserve, ready to move quickly to defend a threatened link in the chain.

To be successful, a policy of deterrence also needs to have a credible threat of retaliation after the fact, and here, too, ground forces could help. At present, the U.S. weapons that can launch a precise retaliatory strike are located on increasingly vulnerable forward air bases and aircraft carriers. The Pentagon plans to address this problem in part by building new submarines and long-range stealth bombers, but the cost of such hardware is high, especially given their relatively modest payloads. Ground forces, by comparison, may offer a cheaper way to provide additional firepower. Unlike air and naval forces, ground forces do not need to return to distant bases in order to rearm. They can store far more munitions than even the largest bomber or warship, and they can place them in hardened bunkers that are better shielded from attack.

Moreover, in the event of a conflict, the PLA would benefit from a particularly asymmetric advantage: its large force of land-based intermediate- and medium-range ballistic missiles. The United States, as a signatory to the Intermediate-Range Nuclear Forces Treaty, cannot deploy these systems. Yet by equipping ground forces with comparatively inexpensive missiles that conform to the treaty’s range limitations, and by positioning them forward along the first island chain to reduce the cost associated with delivering missiles over extended ranges, Washington and its allies could go a long way toward fixing the imbalance at a relatively low cost. And if ground troops could not physically maneuver rapidly enough to respond to a breach in the island chain’s defenses, those nearby could quickly respond by concentrating their missile fire on the threatened area.

Perhaps the first island chain’s greatest vulnerability is the U.S. battle network—the critical systems that handle everything from directing and tracking troops and supplies to guiding weapons. This network currently relies heavily on satellites and nonstealth unmanned aerial vehicles, both of which the PLA could target. The best way to reduce that risk would be to establish a communications network of fiber-optic cables buried beneath the ground and the seabed along the chain, allowing disparate forces to safely receive and transmit data from hardened command centers on land. Island-based air defense and sea-denial forces, as well as antiship minefields, could protect the cable lines running between the islands.

THE ART OF THE POSSIBLE

As with any operational concept, Archipelagic Defense faces hurdles. Two of the most prominent are fiscal and geopolitical: the prospective cost and the willingness of states along the first island chain to cooperate. But despite the price tag of a new posture, the defense community in the United States is beginning to realize that current projected cuts in the Pentagon’s defense budget do not square with today’s increasingly dangerous security environment. The National Defense Panel, a bipartisan group of U.S. defense experts, recently recommended that the Obama administration and Congress restore defense spending to the levels projected in the Pentagon’s original budget for fiscal year 2012. Adopting that recommendation would substantially increase the Pentagon’s resources over the next decade.

The Pentagon can also make the argument that investing in Archipelagic Defense could yield future returns beyond the western Pacific. For example, the so-called AirLand Battle concept, which was developed in the 1970s and helped deter a Warsaw Pact attack on NATO, succeeded not only in central Europe; the United States and its allies also relied on it, in modified form, during the 1990–91 Persian Gulf War. Similarly, the Pentagon could employ many of the capabilities associated with Archipelagic Defense to defend other critical regions, including allies and partners near the Persian Gulf and the Baltic Sea.

If the Defense Department cannot secure budget increases, it can still make changes to better match its overall posture to the current security environment. To cite but one example, the Pentagon still earmarks a significant number of ground forces to defend South Korea from a North Korean attack. Yet a large-scale invasion is unlikely; the greater threat is that Pyongyang could launch a strike with missiles armed with nuclear or chemical warheads. In any event, South Korea has a population that is twice as large as its enemy’s and a per capita income that is more than 15 times as large. Seoul can and should shoulder a greater portion of the burden of its own defense against a traditional ground invasion.

Even with the right resources, dealing with a welter of regional allies and partners will undoubtedly prove challenging. U.S. ground forces would have to play different roles depending on the country. Japan, with formidable capabilities of its own, could bolster its ground defenses without much U.S. support. By contrast, U.S. ground forces would probably need to take on a larger role in the Philippines. In both countries, a greater U.S. ground presence would provide a level of assurance that air and maritime forces, which can be quickly withdrawn, cannot. Taiwan, meanwhile, given the absence of diplomatic relations with the United States, would have to act with little or no assistance.

Several countries, Japan and Vietnam in particular, have already suggested that they are serious about fielding the kind of robust defenses that would be required for Archipelagic Defense. Other states beyond the first island chain, including Australia and Singapore, appear inclined to provide basing and logistical support. But just as it took NATO well over a decade to establish a formidable conventional deterrent to the Warsaw Pact, the United States and its allies cannot establish Archipelagic Defense overnight.

Committing to the strategy now would have the advantage of allowing Washington and its friends to spread the expense of fielding such forces over time. In the meantime, given the region’s ongoing military competition, the United States and its allies along the first island chain must make a persistent, sustained effort to preserve regional stability and prosperity. Of course, Archipelagic Defense would provide no more of a panacea against all forms of Chinese aggression than NATO’s conventional deterrent solved the problems once posed by Moscow’s wars of national liberation and nuclear buildup. But establishing such a posture would represent an essential—and long-overdue—first step in counterbalancing China’s revisionist ambitions.