Where did you dream up this fantasy? The Marine Corps was formed a month after the Navy was created in 1775. The British have had Marines since time began.
And the Greeks, Persians and Romans before then. Naval Infantry.
Marines aren't supposed to do the jobs of the Army in our Order of Battle. The Army is the Senior Service and all other Services, at this time, exist only to support the Army.
In 1775, Navy Ships lashed together with the enemy during a Sea Battle and commenced to beat the shit out of each other and slash or stab each other until one or the other gave up. That's what Marines were for. Sometimes they'd have Sailors in the rigging as snipers but they were good for one shot only. (Try reloading a muzzle-loader while friggin in the riggin).
And oh, idiot 'historians' say that the Brits used smaller ships to defeat the Spanish Armada in 1588. Horse manure. In those days, Navies had YUGE guns that were loaded before they left home port, engaged the enemy and were then incapable of re-loading at Sea. Too big, too cumbersome. The Brits used smaller guns capable of being re-loaded at Sea and shot the shit out of the Spanish when they tried to lash-off and board. Academics..... More like dumbasses.
I'm not knocking the Marines. People just gotta understand, they are not the main fighting force of the United States on the ground. They just aren't. There have been major 'battles' over that since their inception. The Army, rightly, sees them as redundant and, sometimes, an impediment. The Navy sees them as indispensable. They don't like Army Generals telling them what to do, how to handle their ships, where to place them and when a Beach Landing is involved, telling them how to handle that.
The Marines have always had to fight for their very existence. They were disbanded for a long time back in the day. So they've always tried to prove they could 'Do More With Less' which often led to their Alligator mouths over-loading their Canary asses (no offense intended). Again, no knock on the average Marine but on their Higher-ups who learned their Land Warfare at -- Annapolis!
The Marines have their place in our Order of Battle. An important one but there's nothing they can do that the Army can't do. And that's what bothers them. In fact, I believe the Army made more Beach Landings in WW2 than the Marines. Normandy, Sicily, and I think The Philippines, Okinawa had some Marines but it was mostly Army and under Army control. MacArthur used mostly Army for his multiple Beach landings in WW2.
IOW, the Marines could disappear tomorrow and we wouldn't even notice. Specialized Army Unites could take their place. But it would suck for morale
We also use them as the Country's Gendarme. If some pip-squeak country is acting up, we can send in some Marines and nobody gets too excited about it. It's like, "Oh, it's just some Marines

" But if we send in the Army, people get nervous.
There is so much wrong in that post, I don't know where to begin.
Marines make headlines.
The Army makes History
Anything else I can help you with?
