To look at it now I think it is somewhat amazing that the most powerful man in the world had so many people that all had the goods on them that could've brought him down or used him to blackmail him to get the President to layoff on their illegal operations. It is also somewhat amazing that a President of the United States could be so irresponsible with not only his own personal life, but then risk not only his own political career which is his business. But allow for that it effect how he did his job as President of the United States and having to make his own personal affairs part of his administration's business.
But even with all of Jack Kennedy's personal baggage, if anything his administration was tougher on people who had the goods on him, so to speak like the Italian mafia and actually went hard against the mafia and put forward policies that brought down the mafia over the years. The mafia could've told President Kennedy "we have the goods on you, so you better not mess with us, or we'll release what we have on you to the media". They had the goods on JFK, but JFK's brother Robert Kennedy was a different story where they didn't have anything on him. And RFK was also Attorney General of the United States. And his Justice Department went after the organize crime real hard.
You could say that Jack Kennedy was simply too irresponsible to be President of the United States. That his private life was simply too dangerous for him to be President. And again if his private life were public back then, he probably doesn't get elected President and I'm not sure he would get elected President today with the same lifestyle. Because his private affairs wouldn't of been private and the people would really know what kind of man JFK was.
But the fact is as President he was very responsible in the job and in the White House, (when he was working) and his Justice Department actually went hard and brought down people who could've really hurt him politically. And I'm sure part of that had to do with the fact that he had the goods on some of these organize crime people as well. Similar to Bill Clinton the man in public was much different from the man in private. The man in private is reckless, but the man in public is responsible and does his job the best that he can do it.