Because the army an navy couldn't cut it by themselves. America needed a force that could deploy rapidly and take down the enemy
We Are the Marines was created in 1942.
Call Out the Marines was created in 1941.
The Marines Are Coming was created in 1934.
Mumbai Marines was created in 2011.
Metal Marines was created in 1993-12.
Spanish Navy Marines was created in 1537.
Chiba Lotte Marines was created in 1950.
Royal Marines Division was created in 1940.
Little Marines - film - was created in 1991.
Royal Marines A.F.C. was created in 2008.
Corps of Colonial Marines was created in 1808.
With the Marines at Tarawa was created on 1944-03-02.