But then going on to complain himself about how his job is so much harder feels like he's not taking his own advice.

I have great respect for those who serve in the military. But I also have great respect for those who train for 8 years to be a doctor. To imply that those who fight for our country are somehow more entitled than other professions to complain or take credit for serving the country comes across as egotistical. I don't think that's what he meant. But it could be easily read that way.

A better way of saying it would have been. "I hear you bro. I've been out here in 110 degree heat getting shot at and it's hard. But you'll get through." We all serve our country in different ways. And what's hard for one guy isn't always hard for another.