It's easy to forget that the military trains all sorts of people to do all sorts of useful things to support its main function. I've hired lots of ex-military people for construction jobs and they almost always outperformed civvies.
A long time ago, they used to be the only guys with tattoos; more recently, they were the only ones without them.
I noticed they're all wearing hardhats and safety goggles all the time. Getting shot at is probably less dangerous than roofing anyway.