You know when Trump said "[McCain] isn't a war hero. He IS a war hero because he was captured. I don't like people that were captured."?
McCain probably thought something similar, but for Trump. "Trump isn't a president. He IS a president because he was rude to his opponents. I don't like people that were disrespectful to their opponents."
We'll miss you, John McCain.
(P.S. If you ran in 2016 against Hillary and Trump, I probably would've voted for you, assuming you didn't choose Crazy Sarah Palin as your VP, or any insane Republican, for that matter)