Approximately 220 South Korean Marines and 220 U.S. Marines pushed through the snow and bitterly cold air together in early December during a joint training exercise. The three weeks of training in sub-zero temperatures happen every year, this time at next year’s location for the Olympic Winter Games. The Marines pushed their bodies and honed their tactical expertise, training in hand-to-hand combat, conventional PT exercises like jumping jacks and push-ups (shirtless) in the snow, team building exercises and even tactical skiing (yeah, I said it — tactical skiing with rifles and balaclavas and everything).

The Marine Expeditionary Force told a South Korean news agency, Yonhap, that, “This exercise has been held with a focus on enhancing the combined combat capabilities of the South Korean and U.S. Marine Corps in winter war conditions under which temperatures drop down to about minus 20 C.”

U.S. Marines from III-Marine Expeditionary Force from Okinawa, Japan, run on the snow to attend a joint military winter exercise with South Korean Marines in Pyeongchang, South Korea, Tuesday, Dec. 19, 2017. More than 400 Marines from the two countries participated in the Dec. 4-22 joint winter exercise in South Korea. (AP Photo/Ahn Young-joon)

The Marines, from the III Marine Expeditionary Force, hail from their station in Okinawa, Japan. They provide

the United States with a forward-deployed force in readiness in the Pacific Theater, as a globally responsive, expeditionary, and fully scalable Marine Air Ground Task Force (MAGTF), capable of generating, deploying, and employing forces for crisis response, forward presence, major combat operations, and campaigns.”

Up in Okinawa, they generally serve to uphold the “Treaty of Mutual Cooperation and Security between the United States and Japan,” a treaty that the United States has held with Japan since it was signed in 1952, essentially tying the fates of the two countries together. No treaty has lasted this long since the 1600s.

From this staging point, the III Marine Expeditionary Force has operated all over the world. Of course, they participated in both the wars in Iraq and Afghanistan, but they have also played peace-time roles too. They have conducted multiple operations in support of relief efforts after typhoons or earthquakes hit southeast Asia hard. Humanitarian and disaster relief has been a hallmark of their presence in east Asia.

For those not as familiar with the geography of the area, Japan stretches to the east of North and South Korea. These Marines’ base in Okinawa lies directly south of South Korea. As tensions seem to continuously rise with North Korea, these exercises are not only for training and team-building purposes, but are also displays of power and readiness for the eyes of Kim Jong Un and his military. These drills are there to remind him of the immense forces that surround him; we saw this in greater proportion in November with the U.S. Navy’s awe-inspiring display of firepower on the ocean nearby.