The Navy is the most prominent branch of the military in America because America has been, and always will be, a naval power. I believe that over time the Navy will be the one spearheading our quest for space, not the useless dandies it in the Air Force.
A glance at a globe supports what you said. Two great oceans, the Pacific and Atlantic, on both sides of us. Any attempt to defeat and take over America by forces abroad, will have to come by way of the sea. A global map proves the Navy is America’s first line of defense.