The United States Marine Corps is America's amphibious force-in-readiness This role stems from the country?s position as a maritime nation with worldwide interests.

Marines and the Marine mission have long been associated with the sea and with amphibious capability. The word "marine" itself comes from the Latin marinus, meaning "related to the sea. The "amphibious" comes from the Greek amphibian - literally. "living a double life. "

Marines today have a dual responsibility. To serve on land, sea and in the air; and to develop and exploit the advantages of readiness and amphibious capability.

The capability to protect sea power ashore is still an essential element of national strategy. This includes the ability to execute amphibious landings. The Marine Corps is expressly charged with this task.

Marine amphibious forces, operating with the fleet, provide the nation's only major capability to forcibly enter any hostile area from the sea. They can proceed without interruption from a naval to land campaign with the ability to build up a strong fighting force. They are a combined force having all the all the elements of combat power.

Their versatility and responsiveness lend a significant dimension to the options available to the National Command Authority in time of crisis.

Today's Marine Corps emphasizes three fundamentals: readiness, versatility, and the totally integrated capabilities of the Marine air-ground team. Operational readiness is the Marines' top priority. It is the cornerstone of the Marine Corps' existence as a fighting military organization.

Versatility refers to the Marines' method of tailoring air-ground teams in size, structure and striking power to meet worldwide needs. It ensures, too, that Marine Forces will remain flexible enough at all times "to perform such other duties as the President may direct ..." a mission deliberately in general terms to permit the Marines to respond swiftly, when needed as a general purpose force.