Are you buying this??
Well, my taxes go to pay for it, so, in that sense, I am. There is the added thought that security for out forces present in theater might be a good idea. (I can't say I believe in "moderate" Muslims, and don't fully trust any).
But some of these gee-whiz weapons systems are maintenance intensive. It takes 30-40 man hours of maintenance for every flight hour of an F-22, for instance. The F-15, from 12-25 hours, the F-35 (newer) from 5-15 man hours per hour of flight time. That's just the aircraft. Missiles don't fly over to their launchers and load themselves in. All of this takes people, to unload, transport, load and prepare to fire. People to maintain the radars and man them 24/7, people to stand guard on all that.
Back to combat troops, which is what you are clutching pearls and having vapors over, yes, there are going to be some, or all the enemy would have to do is go gather around and destroy our people working on the rest of this stuff. And that's not to mention those doing physical acts of damage control on the sites where ordnance got through.
This is no small operation, and it is spread out, so 50,000 doesn't seem outrageous.