SEOUL, South Korea
— U.S. Defense Secretary Robert Gates pledged Oct. 22 that the United States would use its missile defense shield to defend South Korea against North Korean missiles in the case of war on the Korean Peninsula, as part of its extended deterrence.

It is the first time that detailed plans of the increased U.S. deterrence capability have been revealed and even stipulated in a joint communiqué since 2006, when defense chiefs from both nations first addressed the issue.

“Secretary Gates reaffirmed the U.S. commitment to provide extended deterrence for the RoK [Republic of Korea], using the full range of military capabilities, to include the U.S. nuclear umbrella, conventional strike, and missile defense capabilities, said the communiqué issued at the end of the Security Consultative Meeting

 between Gates and his South Korean counterpart, Defense Minister Kim Tae-young, citing the acronym of South Koreas official name. “Minister Kim conveyed his appreciation for the U.S. commitment and both sides agreed to work closely together to enhance the effectiveness of extended deterrence.”

South Korea has not joined the U.S. regional ballistic missile defense system on which Japan is cooperating, and instead is on track to build its own low-tier missile shield, involving Aegis destroyers and refurbished German Patriot Advanced Capability-2 interceptors, by 2012.

Under the extended deterrence, for example, the U.S. military would use its Aegis ship-based ballistic missiles to intercept North Korean missiles, military analysts here say.

Tomahawk cruise missiles could be launched from nuclear-powered submarines to strike targets, or the U.S. Air Force could send B-2 and B-52 bombers and fighter jets carrying nuclear bombs to neutralize nuclear facilities in North Korea, they said they expect.

“The latest U.S. pledge is a reflection of the firm U.S. resolution on North Korea as well as a security assurance for the South Korean people,” said Baek Seung-joo, a senior researcher at the Korea Institute for Defense Analyses.

Notably, Gates said in the communiqué that the United States would use not only capabilities that are on the peninsula, but also “globally available U.S. forces and capabilities that are strategically flexible to deploy to augment the combined defense in case of crisis.”

Previously, the U.S. military had only referred to reinforcement of troops from the U.N. Commands rear bases in Japan in case of an emergency here.

Observers construed Gates remarks as a response to a lingering concern here that the 2012 transition of wartime operational control (OpCon) of South Korean troops from U.S. to local commanders would result in a smaller U.S. military role, and could tip the military balance between the two Koreas.

Under a 2007 deal on command rearrangements, the U.S. military on the peninsula is to shift to an air- and naval-centric supporting role, with the South Korean military leading main combat operations in the event of a conflict. The South Korean-U.S. Combined Forces Command (CFC) is to be deactivated, and two separate theater commands for each military will be put in place here.

As for a possible readjustment of the OpCon transition timeline, Gates said the transfer would occur on schedule — April 17, 2012 — with top defense officials from both nations regularly assessing security conditions on the peninsula.

Gates and Kim reiterated that they would not accept North Korea as a nuclear weapon state, accusing the communist regime of violating U.N. Security Council resolutions and six-party denuclearization agreements by engaging in missile test firings and a nuclear test in April and May.

“North Korea’s emerging nuclear weapons programs have a destabilizing effect both regionally and internationally,” Gates told a joint news conference following the Security Consultative meeting

 at the Ministry of National Defense here.

Kim acknowledged the allies were developing contingency plans on North Korea.

“In regards to the contingencies and unstable situations, the RoK and the United States will do all they can to make sure there are no negative effects as a result of such events to the peace on the Korean Peninsula,” he said.