[Rummyfan]

As a SEAL, he is member of the US Navy, not US Army or US Marines.

There are Marines in the SEALs.

[A.A. Cunningham]

There are Marines in the SEALs.

Source?

[Mr. Wright]

U.S. Navy SEALs are an elite unit, more exclusive and harder to be admitted to than the U.S. Marines.

The United States Marine Corps (also known as USMC or Marines) is one of the 5 branches of the U.S. military under the Department of Defense. It was created in 1775 as a special service. Although it is part of the U.S. Navy, it has its own special structure. Navy SEALs on the other hand are the U.S. Navy’s main special operations force. They’re part of the Naval Special Warfare Command (NSWC) and are the maritime component of the United States Special Operations Command (USSOCOM). “SEAL” is derived from their capacity to operate at SEa, in the Air, and on Land – but it’s their ability to work underwater that separates SEALs from most other military units in the world.