It’s not even just the fact that he served that makes him a hero but also:
- the fact that he wanted to enlist but was denied due to a leg injury, so he waited for it to heal and came back a year later and enlisted
- he joined THE MARINES of all branches, including both Ranger School and jump school.
- that he saved the lives of multiple men in the middle of a brutal firefight, tending their wounds while waiting for evac
- he also took a bullet during battle, and still returned to lead his platoon for a period before leaving 'nam.
The dude is an American hero in every sense of the term. Of course, however, since he’s heading up the Republican-initiated Russia investigation, then he’s a deep state traitor or something.