From what I understand, Kennedy was leaning away from the war in Vietnam. He didn't think it was any our business. So the author may be wrong on that account. I just don't think Kennedy would be a Democrat this day and age. They are just wacko.
Reagan and Kennedy where my 2 favorite Presidents. They share many of the same ideals.
You didn't ask, but I think the worst presidents were Johnson, Nixon, and Carter.