A second Pearl Harbor guided missile destroyer will leave today for duty in the Persian Gulf, where tensions have ratcheted up over Iran's 13-day seizure of 15 British troops.

The USS Chafee will join up with the more than 6,000 sailors and Marines attached to the aircraft carrier USS Nimitz. The carrier and its strike group left San Diego a week ago.

The Nimitz will join the Stennis carrier group and relieve the USS Dwight D. Eisenhower, which is operating in the Persian Gulf.

The Pearl Harbor-based destroyer O'Kane is part of the Stennis carrier group. The destroyers have a crew of more than 350 officers and enlisted personnel.

The recently freed British sailors said there was no doubt they were operating in Iraq's territorial waters when they were seized by heavily armed boats of Iran's Revolutionary Guard.

Chief of Naval Operations Adm. Mike Mullen told CNN he thought U.S. military forces in that situation would have fought against Iranians and would not have been taken prisoner.

"My expectation is that American sailors are never seized in a situation like that," Mullen said. "Individuals and units are guided by the right of self-defense; they don't have to ask permission to take action to protect themselves."

The Navy said Nimitz's arrival will continue the current two-carrier presence in the U.S. Central Command area of responsibility, "demonstrating the U.S. resolve to build regional security and bring long-term stability to the region."

While deployed, the Nimitz carrier group will work closely with allies to support Operation Enduring Freedom, Operation Iraqi Freedom and to conduct Maritime Security Operations.

"We're ready to fight the war on terrorism and support troops on the ground in Afghanistan and Iraq," said Capt. Michael Manazir, Nimitz commanding officer.

Two weeks ago, American warplanes screamed off two carrier decks as the Navy staged its largest show of force in the persian Gulf since the 2003 invasion of Iraq. The exercise was widely seen as a message to Iran.

The destroyer O'Kane took part in the mammoth exercise involving 15 warships and 100 aircraft.

In January, Defense Secretary Robert Gates said the Stennis strike group was being sent to the Mideast as a warning to Iran that it should not misjudge America's resolve in the region.

This is the Nimitz's third deployment to the Central Command area of operations in four years. In mid-2005, Nimitz supported operations in Iraq and throughout the region. In 2003, the carrier flew combat missions over Iraq and supported combat operations during an eight-month deployment.

The Nimitz group also includes the guided-missile cruiser Princeton; guided-missile destroyers Higgins, John Paul Jones and Pinckney; two helicopter detachments and an explosives ordnance disposal unit.