Seoul, South Korea. (September 7, 2023): Kim Jong Un beware. Except for the U.S.M.C, the ROK Marines are the toughest, most disciplined fighting force on earth. In this photo by Sergeant Mario Ramirez, U.S. Marines with 3^rd Battalion, 6^th Marines join Republic of Korea Marines with 3^rd Battalion, 1^st Regiment, 2^nd Marine Division in close quarter urban infantry training during Korean Marine Exercise Program 23.3 at the Rodriquez Live-Fire Complex here.

The American Korean alliance began when North Korean troops, backed by China and the Soviet Union, poured across the 38th parallel into the South on June 25,1950. The United Nations essentially liberated South Korea from invasion with a single amphibious stroke, and the country has maintained a large and powerful Marine Corps ever since. Under the mentorship of the U.S. Marine Corps, South Korea has absorbed the lessons of General Douglas McArthur’s successful amphibious assault at the port of Inchon in the Korean War.

During the war, South Korean Marines earned the dark reputation as “ghost-catching marines” for their invincibility during several key amphibious landing operations. In Vietnam, the ROK Marines were dreaded by the Viet Cong. In one famous battle, a force of 300 South Koreans successfully fended off an entire North Vietnamese brigade with minimal casualties. They were famous for their special style of combat, and ROK commandos sometimes killed Vietcong with karate chops in close-up fights. U.S. Army studies of the South Korean forces that fought in Vietnam noted that the South Korean Marines seized more weapons than American units did in similar operations.

This reputation for fierceness goes a long way toward deterring a future attack from the North. Any future Korean War will require extensive amphibious operations to avoid a costly war of attrition with a North Korean Army estimated to be 1.2 million strong with millions more in reserves. To counter these numbers, South Korea requires all able-bodied men (sorry, no women) serve a two-year stint in the armed forces. Unlike their U.S. allies, South Korean enlistees serve in often poor and aging facilities and are not free to leave the base, even on weekends. They’re given only a handful of leave opportunities during their two-year mandatory service.

Those who volunteer for the Marines are a different breed. ROK Marine training is some of the toughest in the world, rivaled only by the USMC, and discipline is brutal by American standards. Nevertheless, competition to join the ROK Marines is intense for those willing to endure the physical and mentally difficult training. Today, the ROK Marine Corps, with 29,000 personnel, is the key to the U.S.-ROK partnership, one of the most successful bilateral relationships in history. Built upon shared sacrifice throughout the Korean War, the United States and South Korea have been close allies, since 1953.