The biennial Rim of the Pacific Exercise (RIMPAC) 2012 got underway Monday with military leaders from 22 nations at the formal launch in Hawaii.

The U.S. Pacific Fleet hosts RIMPAC in and around Hawaiian waters in the exercise that runs through Aug. 7.

Pacific Fleet Commander Adm. Cecil Haney said, “The theme of capable, adaptable partners resonates here in what is the world’s largest international maritime exercise.”

Building partnership capacity and capability is a major theme of the Obama administration’s revised global posture strategy, as is the new emphasis on the Pacific. The Navy is shifting its main focus, and more ships, to that Asia-Pacific region.

Haney said 22 nations, 40 ships, six submarines, more than 200 aircraft and 25,000 people are participating in RIMPAC 2012, a command statement said.

The exercise is designed to enhance the tactical capabilities of participating units in major aspects of maritime operations at sea. RIMPAC 2012 is the 23rd in the series, which began in 1971.

Haney said RIMPAC is “critical to ensure the safety of the sea lanes and security of the world’s ocean,” as is the ability to improve interoperability and cooperation.

This year’s exercise includes a number of firsts.

Vice Adm. Gerald Beaman, commander of the U.S. Third Fleet, said, “It is the first time in the RIMPAC series that the component commanders are led by other than U.S. leaders. It’s a sign of where we have come with this exercise and we’re excited, each and every one of us to be here and to carry out RIMPAC 2012.”

The exercise includes a humanitarian assistance/disaster relief component, and the Navy will demonstrate its “Great Green Fleet” approach with some surface ships and aircraft running on biofuel blends.  

Japan Maritime Self Defense Force Rear Adm. Fumiyuki Kitagawa, commander of Escort Flotilla Three, said that there were seven new international partners in this year’s exercise, which is the 17th RIMPAC exercise for Japan. For those in the exercise who provided aid to Japan after the March 2011 earthquake and tsunami, he expressed his gratitude.