Depends on the position. There are all sorts of engineering, medical, and other highly skilled positions. These generally don't pay very well relative to comparable civilian positions and carry more risk and inconvenience due to deployment. They get fantastic benefits though, so it's kind of a wash. Good choice for people that fit the lifestyle well.
If you're thinking strictly of infantry and other combat rolls, the training is there, but it's still a skill set. Someone can't just walk in off the street and do it without extensive training (or getting themselves kilt).