More relevant is the considerable Chinese progress in modernizing its offshore maritime capabilities. Most significant has been China's acquisition of advanced Russian weaponry. Russian Kilo-class submarines are difficult to detect and can significantly enhance the likelihood that China could destroy U.S. surface vessels, including destroyers and aircraft carriers. China is also improving its conventional missile capability. Its Russian Su-30s are equipped with air-to-ground missiles that will contribute to its ability to target U.S. surface vessels, and its acquisition of Russian S-300 surface-to-air missiles enhances its ability to target U.S. aircraft operating in Chinese coastal waters.

These new capabilities pose a danger to U.S. naval security. But China's recent acquisitions from Russia also reveal the PLA's limitations. Chinese modernization enhances a coastal sea-denial capability but does not contribute to a blue-water sea-control capability. Its aircraft and short- and medium-range missiles are tethered to Chinese territory. Its next generation of Russian surface-to-air missiles has a limited range of 200 kilometers. And even in its coastal waters, China's capability is at best limited. It continues to lack the sophisticated guidance capability to allow its missiles to strike moving targets at sea, such as a U.S. aircraft carrier, and ballistic missiles are an ineffective anti-ship weapon. Despite the improvements in China's air force, the United States has finished testing and is preparing to deploy the F-22 aircraft, which is far superior to any aircraft in the world, including Russia's most advanced. China's full complement of Kilo submarines may become fully operational sometime in the next decade. At that time, U.S. aircraft carriers and destroyers may well have to operate at a greater distance from the Chinese coast to minimize casualties--but this will not prevent the United States from establishing air superiority along the Chinese coastline. Moreover, advances in U.S. anti-submarine warfare capabilities will degrade the capability of China's Kilo submarines and help sustain U.S. ability to operate in coastal waters.

China is also developing indigenous platforms. For example, it recently launched its first post-Mao submarine, the Yuan class. But the capabilities of the Yuan submarine remain limited. Its hiding and attack capabilities are less advanced than the capabilities of the Russian Kilo, limiting it to a supplemental role in sea denial. China has also completed development of its first post-Mao fighter jet, the J-10. But because the J-10 took over twenty years to develop, it is based on the 1970s technology of the cancelled Israeli Lavi jet program, and it remains beset with problems. It is an inferior aircraft compared to both of the aircraft China has purchased from Russia and compared to U.S. carrier-based aircraft in the western Pacific. Although Chinese manufacture of Yuan-class submarines and of the J-10 represent major breakthroughs for the Chinese defense industry, they rely on imported technologies. They are only breakthroughs because the industry began from such a backward position in the aftermath of the Maoist era. China's indigenous missiles are also fairly primitive. Its anti-ship cruise missile technologies still reflect 1960s and 1970s capabilities, and its development of long-range naval surface-to-air missiles for ship defense confronts enduring problems.

In the end, China's development of a coastal-water sea-denial capability neither undermines U.S. sea control nor contributes to a war-winning capability. True, Chinese modernization has transformed the cross-strait balance, but this was all but inevitable once rapid economic development began. In any case, Taiwan has never depended on its own capabilities for security, but rather on the likelihood of U.S. intervention and its deterrence of a Chinese attack. In this respect, Taiwan is as secure as ever.

Improved Chinese capabilities will expose U.S. forces to greater losses than five years ago and will thus complicate U.S. naval operations. Nevertheless, U.S. aircraft deployments at Kadena Air Force Base in Japan and in Guam and the ability to deploy multiple aircraft carriers in East Asia with port facilities in Japan and Singapore assure the U.S. Navy of continued maritime supremacy in the western Pacific. And China's recent advances have not improved its ability to operate in sea lanes of communication. According to the 2005 Pentagon report on Chinese military power, the Chinese navy is vulnerable to attack when it patrols in the Malacca Strait and among the disputed territories in the South China Sea. U.S. maritime supremacy also enables the United States to plan for its fighter planes and bombers to carry out strikes against Chinese territory and place at risk Chinese coastal and interior civilian and military assets, including ships remaining at port.

The outcome of any war between the United States and China would be devastating for Chinese interests. As General Zhu Chenghu recently observed, China has "no capability to fight a conventional war against the United States." Indeed, China would face near inevitable defeat, with the military, political and economic costs far outweighing any costs incurred by the United States. China would risk losing its entire surface fleet, and it would expose its coastal territory, including its port facilities and its surface vessels at port, to U.S. air and missile strikes. The economic costs would also be devastating. China would lose access to Western technologies for many years after the war. It would also lose its peaceful international environment and risk its "peaceful rise" as its economy shifted to long-term war-footing and its budget contended with a protracted U.S.-Chinese arms race, undermining domestic infrastructure development and long-term civilian and defense technology development. Finally, the political costs would be prohibitive. A military loss to the United States could well destroy the nationalist credentials of the Chinese Communist Party and cause its collapse.

Nowhere is Chinese caution more evident than in the Taiwan Strait. Despite the advances in Chinese capabilities, the mainland has been exceedingly tolerant of Taiwan's movement toward sovereignty. Over the past five years Chen Shui-bian's rhetoric has amounted to an informal declaration of independence. Much to the concern of both the Bush Administration and Beijing, Chen has frequently suggested his intention to replace the current constitution with a new constitution that would establish de jure Taiwanese independence. In response, China has fulminated, threatened, deployed its forces and rattled its sabers, but it has refused to use force, despite the leadership's conviction that Chen is determined to move Taiwan toward formal sovereignty and Chen's apparent disregard for Chinese resolve. Chinese leaders know that should there be a war in the Taiwan Strait, the U.S. Navy would intervene and the cost to China would be intolerable. Only if Taiwan actually declares de jure independence, thus challenging the Communist Party's domestic survival and leaving Beijing no choice but to retaliate militarily, would China risk war with the United States over Taiwan.

But the status quo is an insufficient indicator of future trends. What are China's strategic intentions, and what are the implications for U.S. maritime security? Thus far, China has cautiously developed its naval capabilities. In many respects its strategy resembles the Soviet Union's response to U.S. maritime dominance from the end of World War II to the 1970s. To compensate for its limited naval capabilities, Moscow deployed attack submarines and aircraft to push U.S. maritime forces away from its coastal waters.

Only when Moscow expanded its Pacific fleet and attempted to develop blue-water power-projection platforms did Washington begin to assess the Soviet Navy as a serious threat. In much the same way, for China to pose a threat to U.S. security it must move beyond coastal sea-denial capability and develop a similar blue-water power-projection navy. However, China faces considerable long-term constraints in pursuing such an objective. First, it has to overcome the technological obstacles. Unlike sea-denial capabilities, power-projection capabilities cannot be imported; they must be developed indigenously. No country will sell China a capable carrier and the necessary aircraft and support ships. Moreover, maintenance of advanced carrier technologies and effective management of a carrier task force require a large contingent of civilian and military personnel with highly advanced training. The limited capability of China's Yuan-class submarines and J-10 aircraft reflects its ongoing struggle to develop 21st-century weaponry, including advanced aircraft for deployment on carriers. Indeed, Pentagon officials recently testified that China still must overcome many obstacles before it can use its existing Russian weaponry to improve its operational capabilities. It has yet to develop the personnel that can maintain the equipment and use it to its full potential. Chinese submarines have the worst safety record in the world; in the past three years the Chinese navy has lost one submarine and disabled another.

In addition, China must contend with a daunting geopolitical environment in which it has 13 land neighbors, including Russia, which Chinese leaders cannot and have not dismissed as a future rival, and India, as well as smaller but nonetheless potentially capable states. It also faces multiple disaffected minority movements on its periphery. Should China seek blue-water capabilities, it would have to simultaneously maintain its costly effort to ensure territorial security. Finally, any Chinese effort to develop power-projection capabilities must consider the U.S. response, which would likely be a determined commitment to victory in a naval arms race. The outcome of this race would significantly reflect overall economic capacity. According to the Pentagon, if China sustains its current economic rate of growth until 2025, its GDP would still be approximately 30 percent of the U.S. GDP in 2025.