Long days are spent doing exercises designed to help them in the uncertain days ahead. There's live-fire weapons training. Hand-to-hand combat. Singing.
Soon the 55 Tongans will deploy to the Middle East to assume security duties at Camp Victory, near the Baghdad airport.
To the Tongans will go the responsibility of guarding the Multinational Coalition Force command center at Al Faw Palace -- an inviting target for insurgents -- as well as the rest of the sprawling base.
Tongan Capt. Tau Aholelei said his troops were eager to get to Iraq.
"We're aware of the risks," he said. "The harder we train, the smoother it will work out when we get there." Aholelei translated for his troops, most of whom are not fluent in English.
In keeping with their cultural tradition, the Tongans enjoy singing and have a variety of war chants and love songs. Their days begin with prayer and end with song.
On Tuesday, in the middle of a vigorous morning of bone-crunching martial arts training, the Tongans broke into song, including a fight song that dates to World War II and beyond.
A rough translation of that song includes this refrain:
Although we go through the hardship of training
Even though we must take cover from the rain
We can stand and fight for anything.
The Marines burst into applause at the end.
Tonga has a relationship with the 1st Marine Division that stretches to World War II and the battle at Guadalcanal, where Tongans fought alongside Marines against the Japanese.
In late 2004, Tongans provided security at Camp Blue Diamond, the 1st Marine Division's headquarters in Ramadi, Iraq.
When insurgents managed to land crude missiles in the Blue Diamond grounds, the Tongans broke into a war dance to show that they were not afraid.
"Having a warrior background helps a lot," said Marine Sgt. George Moleni, 28.
Moleni, a champion arm-wrestler, was born in Tonga, went to Hawaii as part of a Mormon mission as a teenager, and ended up enlisting in 2000. He is the Marines' liaison to the Tongans and will join them in Iraq.