United States Marine Corps off-base, except in transit to and from their place of duty and in the event of an emergency. As in any military organization, the official and unofficial traditions of the Marine Corps serve to reinforce camaraderie and set the service apart from others. The Corps' embrace of its rich culture and history is cited as a reason for its high "esprit de corps". The "Marines' Hymn" dates back to the 19th century and is the oldest official song in the United States armed forces. The Marine motto "Semper Fidelis" means "Always Faithful" in Latin, often appearing as "Semper Fi"; also
Organization of the United States Marine Corps Marine forces assigned to Unified Combatant Commands, Marine Corps Security Forces guarding naval installations, and Marine Security Guard detachments at American embassies. Under the "Forces for Unified Commands" memo, Marine forces are assigned to each of the regional unified combatant commands at the discretion of the Secretary of Defense and with the approval of the President. Since 1991, the Marine Corps has maintained component headquarters at each of the regional unified combatant commands. Marine Corps Forces are further divided into Marine Forces Command (consisting of II Marine Expeditionary Force) and Marine Forces Pacific (I Marine Expeditionary Force and III Marine