Ray Kelly, the police commissioner who should be the next mayor of New York, seems to show you his best in the city’s worst moments. This he did the other day when he stood at a podium with the department crest in front of him and uniforms behind him, speaking of the murder of an 8-year-old from Brooklyn named Leiby Kletzky.

Always when something like this happens, this kind of monstrous and unspeakable tragedy, a death in the city feels more like a death in the family.

So here was Kelly asked to stand and speak about it to the city. He is not loved by everyone in his own ranks, but somehow is trusted more than any New York politician we have right now. Here was Kelly talking of blood on a refrigerator door of a man named Levi Aron and cutting boards and Dumpsters.

And even as the commissioner spoke in the clipped language of the squad room, he brought a painful humanity to it all as he spoke of the randomness of the boy being pulled off the street as he walked home from camp, as if a hand reached out from hell.

“It was just happenstance,” he said in a quiet voice, “and a terrible fate for this young boy.”

Theodore Roosevelt was a New York police commissioner who went on to become President. No city police commissioner has ever gone on to be mayor. Kelly ought to be the first, especially when you look at those lining up already to succeed Michael Bloomberg in a couple of years, and when you remember that Anthony Weiner once seemed to be at the front of the line. Kelly will turn 72 in 2013, but there is an expression from sports that covers that one: He plays younger. And he is a better commissioner now than he was the first time around in the 1990s, in a far more dangerous world.

Nick Scoppetta worked closely with him when Scoppetta was fire commissioner, and if you know anything about the routine turf wars between the NYPD and the FDNY, you know that is hardly routine.

“Ray Kelly has done a splendid job, obviously, as police commissioner,” Scoppetta was saying Sunday. “He has fully realized the possibilities of the job and the responsibilities of it in the modern world, and by that I mean the post-9/11 world.” Then Scoppetta said, “It goes without saying that Ray Kelly is a New Yorker of the first and highest rank, in all the important ways.”

Kelly is not a politician, even if he has always been able to handle himself in the corners, both here and in his big Washington jobs, working as under secretary for enforcement at the Treasury Dept., later as commissioner of the Customs Service. And at a time when most politicians are held in such low esteem, the fact that Kelly is not a career politician is something you put high up on his résumé. Or in lights.

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