I don’t understand the first part of your response. One does not “believe” or “disbelieve” facts (though perhaps the modern right wing thinks such a thing is possible). It’s documented fact that Kennedy had many sexual affairs while president. It’s an equally documented fact that he stared down the Russians in 1963 and the Russians blinked. So it is a proven fact that a person can do both.

Does that mean it’s a desirable situation? Probably not. Of course you have the right to vote for whoever you want, and the 2016 election proved that many Americans are happy to put a serial adulterer and accused rapist into the White House. Perhaps people didn’t know these things about Kennedy in 1960, but they were certainly well known about Trump in 2016.