In an interview broadcast Sunday on C-SPAN, McCain spoke on the 50th anniversary of his being shot down over North Vietnam, an event that led to his capture by communist forces and a five-and-a-half-year stay in the infamous "Hanoi Hilton" prison.
"One aspect of the conflict, by the way, that I will never ever countenance is that we drafted the lowest-income level of America, and the highest-income level found a doctor that would say that they had a bone spur," McCain said.
This was an apparent reference to the diagnosis that allowed Trump to be medically disqualified for service in 1968. "That is wrong. That is wrong. If we are going to ask every American to serve, every American should serve," said McCain, the son of an admiral who refused an offer of early release by his captors despite being tortured.