Difference between the Navy and the Marines

February 13, 2017 by Editorial Team

While their organizational names hint at sea-borne vessels such as aircraft carriers and nuclear submarines, the Navy and the Marines are separate organizations responsible for defending the nation’s interests and sovereignty. Let’s highlight their differences to find out more about them.


US Navy personnel aboard an aircraft carrier

The United States Navy, or USN, is a branch of the US Armed Forces whose primary responsibilities are to prepare combat-ready naval forces, defend the country’s territorial waters (including its allies), and develop and maintain weaponry, aircraft, techniques, and equipment essential to all operations and activities of US naval forces.

The US Navy is the largest and most combat-ready naval force in the world. It maintains the largest fleet of aircraft carriers. As of October 2016, it had 323,792 personnel on active duty status and 108,515 reservists. The Navy boasts 274 battle-ready vessels, along with over 3,700 different aircraft in active service.

Established in 1775, the US Navy can be traced back to the Continental Navy formed during the American Revolutionary War. It disbanded shortly and became a separate division. The US Naval forces then played an important role in blockading the Confederates during the American Civil War. During World War II, they played a central role in defeating Imperial Japan. Their ability to deploy forces anywhere in the world near coastal environments and shorelines make the US Navy a major player in foreign and military policy.

US Marines during field training

The US Marines, or the US Marine Corps (USMC), is the smallest US military branch in terms of size. Despite this, the US Marines have taken on some of the most difficult missions military planners have ever devised. No other US military organization has developed such a military culture that thrives on hardship and challenge.

The US Marine Corps’ primary responsibility is to provide power projection – that is, rapid deployment of US military might into any hostile spot in the world. This is accomplished with the help of US Navy hardware (e.g. ships, aircraft, facilities). They have led countless amphibious assaults to pave the way for incoming American troops. Marines are also responsible for securing and setting up Army and Air Force bases of operations. Complete with close air support and logistical support, a US Marine unit is fully equipped for any mission they may undertake.

In 2015, the US Marine Corps was comprised of 183,787 active personnel and was backed by 38,213 reserve personnel. Marines are usually stationed in Navy ships to provide security. Marine officers receive training at the Naval Academy. The highest-ranking officer of the US Marine Corps is the Commandant of the Marine Corps. He reports to the Secretary of the Navy and is a Joint Chiefs of Staff member.


While both organizations are separate branches of the military, the Navy and the Marines have worked closely in countless military operations around the world.

It is the US Navy’s job to defend the nation’s sovereignty and extend its reach through naval dominance. The US Marine Corps is part of the US Navy, but they are a separate division of the military under the Department of Defense. The Marines’ main function is to project the military power of the US by providing rapid deployment of highly skilled combat forces to any parts of the world with the help of US Navy hardware. The US Navy maintains the largest naval force in the world, while the US Marine Corps is the smallest branch of the military in terms of personnel. Although the Navy and the Marines make up the Department of the Navy, the Marine Corps is a separate branch headed by the Commandant of the Marine Corps. The Navy is managed by the Department of the Navy, headed by the Secretary of the Navy or SECNAV.

Comparison Chart

Defends the country through naval supremacyProjects the might of the US military in any hostile spots in the world
Headed by the Secretary of the NavyHeaded by the Commandant of the Marine Corps
Maintains the largest naval force in the worldSmallest branch of the US Armed Forces and is part of the US Navy