John McCain was a seasoned naval pilot who, amongst other things, ran 23 bombing missions over North Vietnam, was shot out of the sky, captured as prisoner of war, and tortured.
You don’t have to like his politics, but claim that he “never saw combat” is a slur.
Most famous Vietnam era veteran I know who didn’t see actual combat was former 1980s era pro wrestler and later MN State Governor Jesse Ventura (James Janos). Ventura (Janos) was legitimately a member of the US Navy Underwater Demolition Team, and went through its rigorous BUDS training, but he never saw combat.