China says that, like Taiwan, these areas in the South China Sea and the East China Sea are a part of its territory and were taken away when China was weak. Control of these places is contested not just for reasons of national pride, but also because they contain valuable undersea oil and gas, fisheries and some of the world's busiest and most important shipping routes that are used extensively for trade and naval operations by many countries, including the United States.

The Chinese navy reportedly plans to have a refurbished former Soviet aircraft carrier in operation by 2012 for training and developing basic skills; a made-in-China carrier is to take to the seas sometime after 2015. This advance in power projection is expected to have predominantly regional implications.

The U.S. Office of Naval Intelligence completed a study last year of the People's Liberation Army Navy, the official name of the Chinese navy. It noted that although aircraft carriers were viewed in the U.S. as instruments of global force projection, Chinese officials had stated that carriers were necessary for protecting China's maritime territorial integrity.

Shortly after a series of incidents at sea off China's coast between Chinese military and civilian vessels and two different U.S. Navy surveillance ships just over a year ago, the official Xinhua News Agency said that China would not "build an offensive navy cruising the globe." Instead, the Chinese navy would concentrate on its offshore area.

"In order to defend China's territory and sovereignty, and secure its maritime rights and interests, the navy decided to set its defense range as the Yellow Sea, the East China Sea and the South China Sea," Xinhua reported. "This range covered the maritime territory that should be governed by China, according to the U.N. Convention on the Law of the Sea, as well as the islands in the South China Sea, which have been its territory since ancient times."

With a total of around 260 naval vessels, not far short of the 286 ships in the U.S. Navy, China now has 75 destroyers, frigates, amphibious transports and submarines. This makes it the largest force of major warships in Asia, according to the Pentagon's latest report to Congress on Chinese military power.

An increasing number of these ships are technologically advanced and well-armed. However, the Chinese navy still faces many challenges and it is far from matching the U.S. Navy in terms of capability. Both the Japanese and Indian navies can also do some things better at sea than China.

To discourage the U.S. or any other foreign navy from intervening in Beijing's declared sphere of influence around Taiwan and in the South and East China Seas in a crisis, Chinese military strategists have developed a set of weapons and tactics to deny hostile forces access. Among the weapons are submarines that are increasingly difficult to detect and an array of long-range anti-ship missiles that are increasingly difficult to defend against.

The latter include what would be the world's first operational ballistic missile and maneuverable warhead guided by satellite and land-based over-the-horizon radar to strike aircraft carriers at up to 12 times the speed of sound far out at sea. U.S. military officials and analysts regard it as a serious threat to American naval operations in the Western Pacific.

U.S. Defense Secretary Robert Gates on May 3 warned that "the virtual monopoly the U.S. has enjoyed with precision guided weapons is eroding — especially with long-range, accurate anti-ship cruise and ballistic missiles that can potentially strike from over the horizon."

China's anti-ship ballistic missile, with a range of 1,500 km, would be fired from mobile launchers on land. Adm. Robert Willard, the commander of U.S. forces in the Pacific, told Congress in March that China was "developing and testing" the missile. He added that it was "designed specifically to target aircraft carriers." Gates said that such a weapon could potentially put at risk a modern nuclear-powered U.S. carrier with a full complement of the latest aircraft — an asset worth as much as $20 billion. He added that a combination of lethal missiles and stealthy submarines "could end the operational sanctuary our navy has enjoyed in the Western Pacific for the better part of six decades."

It is not the first time that Gates has spoken about this threat. Last September, he said that China's "investments in anti-ship weaponry and ballistic missiles could threaten America's primary way to project power and help allies in the Pacific — particularly our forward bases and carrier strike groups."

The U.S. Naval Institute cautioned a year ago that "the mere perception that China might have an anti-ship ballistic missile capability could be game-changer, with profound consequences for deterrence, military operations and the balance of power in the Western Pacific."

For Southeast Asian states — particularly those like Vietnam, the Philippines and Malaysia that actively contest China's claims in the South China Sea — such game-changing developments will only reinforce their concerns about rise of the Chinese navy and its regional role.

Japan must be equally concerned, even as it seeks better relations with China. The balance of power in the Asia-Pacific region appears to be shifting in ways that make it much less stable — and a lot less comfortable for peripheral countries like Japan and Australia that are both allies of the U.S. and have strong interests in continuing growth and security in the region.