Story highlights John McCain spent five years as a prisoner of war during the war

Donald Trump received five military draft deferments during the Vietnam War

Washington (CNN) Sen. John McCain, in an interview about the Vietnam War, appeared to take a swipe at President Donald Trump when he criticized people from "the highest income level" who avoided the draft by finding a doctor who "would say that they had a bone spur."

Trump, who attended the private New York Military Academy as a young man, received five military draft deferments during the Vietnam War, including one medical deferment after he was diagnosed with bone spurs in his foot.

McCain and Trump have feuded since the businessman-turned-president used an early event in his 2016 campaign to derided the Arizona Republican's military service, claiming he was not a war hero because he was captured during the Vietnam War. Trump refused to apologize and their feud has carried into his administration, where McCain has been one of his most fervent Republican critics on Capitol Hill.

"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 they had a bone spur," McCain told C-SPAN3, American History TV, in an interview about the Vietnam War. "That is wrong. That is wrong. If we are going to ask every American to serve, every American should serve."

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