I agree that JFK is overrated, but in many instances the actual man isn't important to history--his myth is. JFK has become a Legend, and that's fine--a sort of noble grandeur surrounds him. So what if in actuality he was mediocre--people are inspired by his memory and will work for his ideals. And his ideals were solid--freedom-loving and anti-Communist, pro-business, pro-low taxes, individualistic. It may be that his policies never matched his rhetoric, but the advantage of being martyred is that it is your rhetoric that is remembered. A nation needs Heroes to sustain it, and if Kennedy is to become one of them, then I say welcome to the Pantheon.
I give JFK credit for getting through the Cuban Missile Crises without destroying the world. He deserves honorable mention for that.