Air Force Col. Bud Day, having already fought in World War II and the Korean War, was flying his 65th mission over Vietnam, when his plane was shot down and he, after bailing out, suffered a broken arm and injuries to his back and eye. Captured by North Vietnamese soldiers, he was beaten up before becoming that conflict’s only U.S. prisoner of war to escape his captors. After wandering dazed in the jungle for days, Day was captured by the Viet Cong, and he eventually ended up in the infamous Hanoi Hilton, where his bravery and leadership, while enduring 5 1/2 years of relentless torture and starvation, resulted in his later becoming the only American ever to be awarded both the Medal of Honor, the nation’s highest citation, and the Air Force Cross.

During his own 6 1/2 years in that same Hanoi hellhole, Marine pilot Orson Swindle, who had been shot down as he was flying his 205th mission, would lose 75 pounds while being subjected to physical and mental torture. Navy Cmdr. Everett Alvarez, another captured pilot, spent 8 1/2 years, more time in captivity than any other American during the Vietnam War, in the brutal custody of his Hanoi jailers.

I met all three of these remarkable American heroes in early 2000 in New Hampshire. All three were there on their own nickel, volunteering on behalf of the campaign of a fellow former POW, a former Navy pilot whose character they had seen up close during his own 5 1/2 years of suffering in the Hanoi Hilton and who was running for president, Sen. John McCain.

Now, four elections later, the Republican presidential nominee is a man who, during Vietnam, consciously avoided the military draft, has called his successful avoidance of sexually transmitted diseases during his swinging New York days his “personal Vietnam” and has dismissed McCain as “not a war hero.” Donald Trump said: “He’s a war hero because he was captured. I like people that weren’t captured.”

That same election cycle, 2000, the Democratic nominee was then-Vice President Al Gore, who had been one of only a handful in his Harvard class to volunteer for the military draft and service in Vietnam. I asked Gore why he, whose father was an influential U.S. senator, had chosen the U.S. Army. Here is what he said, and it is worth thinking about today: “I came from a small town (Carthage, Tennessee) of 3,000. … If I didn’t go, somebody else would have to go. I knew just about everybody else who was going to have to go in my place. … For me, that sort of reinforces the sense of community and nation that is at the root of why you have a duty to serve your country.”

I recall Gore’s answer when I asked him whether he knew anyone who had died in the Vietnam War. He listed the names of five neighbors: “James Stallings, Jackie Underwood, Charles Holland, Walter Pope and Roy Wills.” These men were all from Smith County, Tennessee, and the names of all five can be found on the wall of Washington’s Vietnam Veterans Memorial. That memorial is a place where Gore had visited more than once but where former House Speaker Newt Gingrich – a fierce armchair commando who, like Trump, had eluded the military draft and who was unable to name anyone who had died in Vietnam when I asked – had never found time to visit.

As John McCain struggles to win re-election in Arizona to his sixth Senate term, fate has cruelly chained him to a national ticket headed by the man who so publicly and so callously disparaged McCain’s valor and sacrifice. For McCain, an iron rule of American politics prevails: In every campaign you are in, there will always be somebody on your side who you wish devoutly were on the other side.