http://en.wikipedia.org/wiki/Lima_Army_Tank_Plant
Problem is we are down to a single plant that can produce M1 tanks. Stop production and the ability to make tanks rapidly deteriorates.
No one needs M1 tanks to maintain order among competing international corporations and the sports-addled sheep they feed off of.
You are correct, sir. No one truly knows what the future holds, or what form the next wars will take. If you over prepare you will be deemed wasteful; if you under prepare you will be counted dead. All we know for sure is that there will always be wars, and we must be prepared to win.