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Huge military exercise highlights 'rebalancing of US policy toward Asia'

Rosie Brown / Yankee-Brown Productions

A U.S. Navy landing craft arrives at Thailand's Hat Yao beach during Cobra Gold 2013, a military exercise involving 13,000 military personnel.

HAT YAO, Thailand -- An ear-thumping explosion reverberates around the bay as a plume of water shoots hundreds of yards into the air.

Two Marine F/A-18 Hornet fighter jets scream by overhead, while Huey and Super Cobra helicopters bank hard, simulating bombing runs. Heavily armed, amphibious assault vehicles churn up the sand as they unleash hordes of U.S. Marines onto one of Thailand's idyllic eastern beaches.

Cobra Gold 2013 -- the largest multinational military exercise in the Asia-Pacific region -- is officially under way.

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A Thai marine waits patiently for instructions in the midday sun during Cobra Gold 2013.

The annual exercise is in its 32nd iteration and involves 13,000 military personnel countries, including Japan and South Korea, as well as observers from China and, for the first time, Myanmar.

For 10 days, these forces will conduct a variety of field exercises, from amphibious assaults and jungle warfare to humanitarian and civic assistance projects.

Leading the exercises are more than 1,000 Marines and sailors from the 31st Marine Expeditionary Unit, part of Amphibious Force 7th Fleet.

Many of these servicemen and women will play a major role in America's new "Asia pivot" defense strategy, which calls for the strengthening of U.S. military power in the region.

"The pivot to the Pacific that President Obama has talked about is a refocusing of assets and efforts after over 10 years of war in Afghanistan and Iraq," said Capt. Cathal O'Connor, commander of Amphibious Squadron 11. "But the actual relationship of being out here in the Pacific goes back to the time of the Civil War."

Cobra Gold itself is a holdover from the Cold War when it was one of the key pillars of U.S. regional security.

'A deterrent'
During the height of the Cold War, the exercise regularly simulated invasions of Thailand from its northern and eastern borders.

Now with U.S. once again focused on the Pacific, Cobra Gold has taken on renewed significance, explained Jon Grevatt, an Asia-Pacific analyst for IHS Jane's.

"It has new purpose to show the strength of military collaboration between the U.S. and its partner nations, creating a deterrent to Chinese and North Korean ambitions," he said.

Tensions have been rising in the region with the dispute between China and Japan over the Senkaku Islands – known as Diaoyu in Chinese -- and North Korea's latest nuclear test.

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Plumes of smoke rise from simulated bombing runs over Hat Yao beach in Thailand.

This strengthening has already begun with the Navy sending a newly upgraded, guided-missile cruiser, USS Antietam, to join the 7th Fleet based in Japan. The Antietam gives the Navy a more sophisticated air-defense system, particularly against ballistic missiles.

More ships will be arriving in the region in the near future as the Pentagon continues its plan to shift around 60 percent of all Navy warships to the Asia-Pacific theater by 2020.

And it's not just the Navy getting in on the action, the Marines have deployed two battalions -- nearly 2,000 troops -- to Okinawa in the last six weeks with more scheduled to arrive this summer. There are now more than 17,000 U.S. Marines based in Japan -- the most in over a decade.

Both Obama and Defense Secretary Leon Panetta have visited Southeast Asia in recent months, reinforcing how critical the Asia-Pacific theater has become to U.S. strategy.

"We all know that the Asia-Pacific is the traffic highway of so many goods and services. A great many things are manufactured in this part of the world," said Rear Adm. Jeffrey A. Harley, commander of Amphibious Force 7th Fleet. "The United States has been a presence in the Pacific for many, many years… and they will continue to be so."

Sheila A. Smith, an expert on regional security in Asia for the Council on Foreign Relations, said that despite the fact China had accepted an invitation to observe Cobra Gold "military exercises always raise eyebrows."

“The president is a Pacific president," she said. "I think he realizes that the region has been overlooked. It’s not threat-based or military-driven. The large part is an adjustment of diplomatic focus."

Rosie Brown / Yankee-Brown Productions

US Marines assault Hat Yao beach during an exercise as part of Cobra Gold 2013.

Matt Stumpf, an expert on U.S.-Asian relations at the Asia Society think tank, added: "I think what’s notable about this year’s exercise is in the context of the rebalancing of U.S. policy toward Asia.

"The president and [former Secretary of State Hillary] Clinton have both spoken in depth on their views that Asia is critical to the United States in the 21st century. And with the drawdown in Afghanistan and the end of the war in Iraq, there was an opportunity in Asia to refocus diplomatic, defense and development tools for U.S. goals in the region."

NBC News Staff Writer John Newland contributed to this report.

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