I believe the marines were originally conceived as a division of the navy to be infantry that fights ship to ship back in the day. Now a days they have marine expidinionary units that go to sea on navy ships and sail around the world so marines can be on the ground as soon as possible if something kicks off. People fight over water and air all the time. Air superiority is key to having the upper hand on the battlefield and total situational awareness. I don't know if you know what you are talking about.