WHILE THE US MARINE CORPS WAS ONE OF THE SMALLEST OF AMERICAN ARMED SERVICES IN WORLD WAR II, ITS CONTRIBUTION TO THE FINAL VICTORY CANNOT BE OVERSTATED. The US Marine Corps may have only comprised 5 percent of America's armed forces, but it suffered 10 percent of all World War II combat casualties. Above all, he amphibious nature of the war in the Pacific imposed on the Marine Corps greater tasks than any it had ever before been called upon to perform. This title details the organization, weapons and equipment of the US Marines of World War II.