I don't think he was a bad president by any definition. And, I disagree that he would not have been re-elected. The country was fascinated with him and his family, and Barry Goldwater was not the most electable person.

He handled the Cuban Missle Crisis extremely well, and the Bay of Pigs fiasco was really an inherited plan of Eisenhowers. Kennedy himself said he learned a valuable lesson about trusting others, and that lesson showed in the missile crisis. He did what he thought was the right thing to do and didn't listen to the advisors.