Bright science and math whiz types like to play with space and quantum mechanics, etc. If they have jobs waiting for them, they study and learn advanced math and physics. Then on their 'gee-whiz' space job, they practice and innovate skills while we are "at peace" that we will need when we need military upgrades.
Aside from the fact that we get terrific spin-offs from the space program that help people in medicine and life, the cold hard fact is that we need to keep these brains occupied and happy so they are there to step in and help when we really, really need them.
I cribbed this idea from someone else, but it makes a lot of sense to me.
Besides, one shipment of H3 from the moon a year can power our whole country for a year. We don't want a Chinese or a French flag sitting on top of the motherload on the moon.