Though if it had been someone who didn't want to rent to a gay couple, a single mom with a different man every week, or an anti-war protestor, he'd be in jail so fast his head would be spinning.
Personally, though, I think a landlord should be able to rent or not rent to anyone they want. This includes veterans. Private property rights have been trampled on for long enough.
"Live free or die: Death is not the worst of evils."