I'd be discouraging the concept that social and bureaucratic jobs are safe places to work for the rest of your days, that you can't ever be fired, and that your job is 100% guaranteed forever onward. Any bumps caused by the incompetence of inexperience are more than made up for in the reduction of incompetence due to laziness and self protectionism.
Yep.
Can you present an argument to the American people that a 10 year enlisted veteran can do something that a new recruit can't?
Sure.
I was a better operator of the nuclear reactors onboard the TR at the end of my enlistment than I was upon arriving onboard the ship. Heck, even after qualifying onboard ship.
In technically-complex matters, of which there are a multitude in the military, experience matters.