# United States Marine Corps The **United States Marine Corps (USMC)** is the expeditionary, rapid-response branch of the armed forces — an amphibious force that operates as part of the Department of the Navy but as a distinct service, specializing in forcible entry, crisis response, and embassy and presidential security. Founded in 1775, it is led professionally by the **Commandant of the Marine Corps**, a four-star general who sits on the [[Joint Chiefs of Staff]]. Marines provide the security detachments at U.S. embassies and operate Marine One, giving the Corps an outsized symbolic presence around the presidency. For the KB, the Marine Corps is mapped here primarily for structural completeness within the [[Armed Forces Hub]], but it carries specific salience around **domestic deployment**: in the 2025 Los Angeles episode, active-duty Marines were mobilized alongside the federalized [[National Guard]], one of the rare modern instances of regular ground combat troops being staged for a domestic mission — squarely implicating the [[Posse Comitatus Act]]. The current Commandant is **Gen. Eric M. Smith**, the 39th to hold the post (since September 2023), who has continued the "Force Design" modernization reorienting the Corps toward a potential Pacific conflict. ## See Also - [[United States Navy]] - [[Joint Chiefs of Staff]] - [[National Guard]] - [[Department of Defense]] - [[Federal Agencies]]