Once across the Pacific, they joined up with the 31st MEU and Republic of Korea troops for amphibious landings during the massive exercise Ssang Yong 16held in sub-zero temperatures in March.
"That type of demonstration of our abilities showed our partners that ‘hey, we are willing to come here, work with you and stay with you through any type of instability’," Henderson said.
From Sri Lanka, Singapore, Indonesia and Malaysia in Southeast Asia to Jordan, Saudi Arabia, the United Arab Emirates and Bahrain in the Middle East, 13th MEU conducted joint training exercises with U.S. partners, allowing foreign services to practice their skills and giving Marines a chance to maintain readiness.
"As you transit across the Pacific, you can get some things done on the ship: shooting, some hand-to-hand combat and a lot of aviation flying, but for the ground units, it has its limits and that’s a known factor," Henderson said.
Participating in Exercise Eager Lion in Jordan last May, for example, the MEU put 600 Marines ashore with all of its mechanized capability: tanks, amphibious assault vehicles, fuel and support vehicles as well as the mechanics that keep them running.
The group functioned on the ground for 20 days, working heel to toe with the Jordanians to bolster border security.
"It had been over two months since they were able to get on the ground and do what mechanized units do, which is maneuver," Henderson said.
In June and July, AV-8B Harriers from the Boxer flew 45 combat sorties over 27 days, striking 20 different targets around Mosul, Iraq, in support of Operation Inherent Resolve.
They struck ISIS machine gun bunkers, mortar positions and fighters attempting to move against the Iraqi security forces -- 1600 nautical miles from the ship.
"It diminished not only [ISIS’] capacity for some of its strengths, which were the ability to shoot indirect fire and the ability to maneuver its fighters, but I think it also encouraged the Iraqi security forces," Henderson said.
13th MEU also was on station to provide contingency support to the United Arab Emirate’s operation against al-Qaida in the Arabian Peninsula in and around Al Mukalla, Yemen, he added.
For approximately 40 days, the MEU/ARG conducted maritime security operations to deny AQAP resupply through the Gulf of Aden, running patrols around the clock in inflatable rigid rubber boats.
"They pretty much knew we were out there, so they were less inclined to move across the waterways to provide supplies, and that was the effect that we wanted," Henderson said.
Though they didn’t run across AQAP, smugglers or pirates on the water, his Marines soon encountered an unexpected situation, however.
Hundreds of refugees in small dhows were attempting to flee Somalia for Yemen across the Gulf of Aden, an event that had not been part of their six-month predeployment training work-up.
"They had been lost out at sea for several days," Henderson said. "We did what naval forces do all the time: we gave them water and food, and pointed them in the direction they were trying to go."
The 13th MEU was deployed with ARG Boxer for a total of 213 days.
They had moved fast and sustained a high tempo of operations over vast distances, and returned home with a sense of accomplishment, Henderson said.
"On this deployment we started off wanting to show them that they could prepare and train themselves to do a task, to do a mission and go somewhere in the world and be able to do it in the most challenging and most chaotic situation," he said.
"They did that."