Chumpy posted a photo of himself? That's hilarious. I posted his actual photo, provided by his cyber girlfriend Toxic TOP.
That sandbox tantrum out of the way, I don't doubt that Chump is a vet of some sort. I've known him for years on another forum and that story has been consistent... "Me vet." I don't recall what branch of the service, length of service, rank, or theater of action (if not state-side), but I have no reason to doubt that he served in some capacity.
That being said, you are absolutely correct that he uses his service as a bludgeon. "Listen to me, I'm a Real American(tm), I AM A VET." He also accuses those who have not served of not being a Real American(tm). So when he supports a piece of shit president, we need to do the same, because he's A VET and KNOWS BETTER than the rest of us.
Notice how Frank states his opinions and points of view, but does NOT use his status as a vet as a club to beat his opponents senseless?