Under the plate glass atop the desk of the commander of U.S. submarines in the Pacific, Rear Adm. Joseph Walsh, is a navigation chart that is revealing.

It maps the waters from Japan and Korea down the coast of China and through the Taiwan Strait and the South China Sea to Indonesia.

That littoral defines the operating area for most of the Pacific Fleet's 25 attack submarines.

In coming months, two newly assigned submarines, armed with guided missiles, also are scheduled to operate in those waters.

Not long ago, that chart on the admiral's desk in his headquarters at Pearl Harbor would have had a wide-angle focus on the deep blue waters of the Pacific as his fastattack (all one word in submarine lingo) boats searched for Soviet submarines and warships during the Cold War. Now the Russian Pacific fleet, lacking money, is mostly rusting at anchor in the Maritime Provinces or the Kamchatka Peninsula.

Today, Walsh says, the primary targets for American submarines are terrorists, particularly those in Southeast Asia. "The submarine," he contends, "is the perfect platform for the war on terror." The admiral, after 29 years in what submariners call the "Silent Service," did not discuss specific operations.

Officers at the Pacific Command and the Special Operations Command, also with headquarters here, have pointed to the island chains stretching across the Sulu and Celebes seas as routes along which terrorists traveled from training camps in the Philippines to targets in Malaysia and Indonesia.

Submarines have two attributes that make them effective against terrorists — stealth and persistence. Unlike surface ships, submarines can stay concealed in the sea, rising to periscope depth to take pictures, to listen to electronic transmissions, and to collect other intelligence. Unlike the airplanes or satellites that pass over a target, submarines can stay on station for weeks or months.

The fastattack submarines, in addition to traditional torpedoes, each are armed with 12 cruise missiles with conventional warheads. A cruise missile is a flying torpedo with stubby wings, powered by a small engine. Guidance systems make them precise. The submarines can also land a small, six-man special operations team to collect intelligence or conducts raids, then return to pick up the team.

The Pacific submarine fleet has had so many missions assigned to it recently that it no longer sends submarines to the Persian Gulf or Arabian Sea to support the war in Iraq. Instead, submarines are deployed there from the Atlantic Fleet.

Moreover, over the next five years, about eight submarines will be reassigned to the Pacific fleet from the Atlantic to bring the ratio up to 60:40, weighted toward the Pacific. Two will be the Seawolf and the Connecticut, the most advanced ships in the fleet. The home ports to which they will be assigned have not been decided yet, said a spokesman for the Pacific submarine command.

The newest addition to the Pacific Fleet is the USS Ohio, which has been converted from a ballistic missile submarine to a ship armed with 154 Tomahawk cruise missiles that can be fired covertly one at a time or in a salvo. When launched near land, the cruise missiles can duck under radar to hit targets before an adversary can react, or they can loiter over a target shortly before striking.

A second guided-missile sub, USS Florida, is expected to operate with the Pacific Fleet in 2008. Each of these ships has a dual crew, called Blue and Gold, to enable them to stay at sea for long periods. The crews will swap places every three months, usually on Guam, the U.S. territory in the western Pacific that is being built into a large naval, air and Marine base.

The new cruise missile carriers also have been configured to carry 100 special operations troops with their weapons and equipment. The Ohio has been equipped with a delivery system to put the commandos ashore and retrieve them, and with a command center in which the commander of an operation could direct operations ashore.

For a special operations campaign, for instance, Ohio could land 10 teams several miles apart along a coast, and the commander of the campaign could communicate with them all from the submarine. The Ohio is now in Hawai'i for training with special operations forces before deploying to the western Pacific next year.

Richard Halloran is a Honolulu-based journalist and former New York Times correspondent in Asia. His column appears weekly in Sunday's Focus section.