are the marines a branch of the navy
United States Marine Corps The United States Marine Corps (USMC), also known as the United States Marines, is a branch of the United States Armed Forces responsible for conducting amphibious operations[10] with the United States Navy. The U.S. Marine Corps is one of the four armed service branches in the U.S. Department of Defense (DoD) and one of the seven uniformed services of the United States.
Marine Security Guard A Marine Security Guard (MSG), also known as a Marine Embassy Guard, is a member of the Marine Corps Embassy Security Group[3][4] (formerly Marine Security Guard Battalion), a battalion-sized organization of U.S. Marines whose detachments provide security at American embassies, American consulates and other official United States Government offices such as the United States Mission to NATO in Brussels, Belgium. The Marine Security Guard was designated MOS 8151, this has changed to MOS 8156.