I see you haven't thought this through completely, like most people who give kneejerk responses like yours.
I guess you were never on a ship deployed for 7-8 months and needing servicing. It's a long way home with an engine casualty. I guess you want us to take weeks to respond to a situation overseas instead of just hours.
Do you remember when the Somali pirates took over the Maersk Alabama. What overseas bases did we use to get our people there to retake the ship? Where do our ship's get their fuel? Where do our planes land to carry personnel and equipment?
Most of the bases where I visited in the Mediterranean are now gone, except for Naples, Sigonella, and Rota. Most of the Army bases in Germany are gone already. We are building bases in Poland to get closer to Russia. Most of the Army forces in Germany will move there because the Germans don't like us as much anymore.
Surely, you could come up with one base to close, so I could shoot down your idea!