United States Marine Corps

The United States Marine Corps (USMC) is a branch of the United States military responsible for providing power projection from the sea, utilizing the mobility of the U.S. Navy to rapidly deliver combined-arms task forces. While the Marine Corps works alongside U.S. Naval forces, it is part of the Department of the Navy for administrative reasons.

Originally organized as the Continental Marines on November 10, 1775 as naval infantry, the Marine Corps has evolved in its mission with changing military doctrine and American foreign policy. The Marine Corps has served in every American armed conflict including the Revolutionary War. It attained prominence in the 20th century when its theories and practice of amphibious warfare proved prescient and ultimately formed the cornerstone of the Pacific campaign of World War II. By the mid 20th century, the Marine Corps had become the dominant theorist of amphibious warfare. Its ability to rapidly respond to regional crises has made it, and continues to make it, an important body in the implementation and execution of American foreign policy.

The United States Marine Corps, with 180,000 active duty and 40,000 reserve Marines as of 2005, is the smallest of the United States' armed forces in the Department of Defense (the Coast Guard, about one fifth the size of the Marine Corps, is under the Department of Homeland Security). The Corps is nonetheless larger than the entire armed forces of many significant military powers; for example, it is larger than the active duty Israel Defense Forces.