Exercise Valiant Shield is one of the largest U.S.-only military training exercises held in the Indo-Pacific. Some 13,000 troops will be maneuvering in and around Guam and the Marianas over the next two weeks.

The major exercise has been held every two years since 2006. Rear Admiral Robert Chadwick II is the director of the Joint Exercise Control Group, and told KUAM News, "The main purpose is to improve the integration between our joint forces in a wide variety of mission sets. And again, we have representation from every service - Army, Navy, Air Force, Marines, Coast Guard, Space Force."

One of the main training events will be live-fire launches of Patriot missiles to begin next week in Palau. "The ability to show that we can operate anywhere, I think, is one of the key things that we're demonstrating there," the admiral said.

Palau is well-known for its strict environmental control policies. Military environmentalist Mark Cruz said they had to convince leaders there, starting with president Surangel Whipps, Jr. "It was a lot of education on what does this actually mean, what are the impacts associated with this. So we were able to articulate those and they were pretty receptive to it and understood and realized that there are environmental control measures in place. Safety is obviously a huge factor that we're considering and once they took it all into account, recognizing the strategic importance of this, they allowed us to proceed," he explained.

Two carrier groups, the Ronald Reagan and the Abraham Lincoln, are part of the training exercise, but the admiral says neither ship will dock here. However, a good number of troops - he was not specific - will come in or are already ashore.

"A lot of exercises we do are with our partners and allies, this one is where we focus on all the services and increasing our ability to operate together in an integrated fashion and its probably one of the best avenues we have to do that kind of joint warfare that is critical," said Chadwick.