That little wedge of green nestled at the corner of Lafayette and Kenmare streets is called Petrosino Square. It was spiffed up recently and makes a perfect spot for city watching—made even nicer with a little local history. First, the name: Lieutenant Joseph Petrosino lived across the street at 233 Lafayette. A tough-as-nails Italian-American cop, he so spooked the Mafia when he traveled to Sicily in 1909 to identify Black Hand gangsters preying on local immigrants that they had him murdered. Look west and there’s more mob history in the little building at 218 Lafayette. That’s where the country’s largest pornography business was run by a Gambino crime family soldier named Robert “DeeBee” DiBernardo. It didn’t help Democratic Party chances in 1984 when it became known that the smut purveyor’s landlord was married to vice presidential candidate Geraldine Ferraro. DeeBee lost his own election when John Gotti had him whacked in 1986. Look east and there’s a Mexican Radio restaurant at 19 Cleveland Place. It used to be La Donna Rosa, a nice Italian joint run by Alphonse “Little Al” D’Arco. He headed the Lucchese crime family until he learned his own execution was in the works. He switched to Uncle Sam’s team in 1991. It was the highest-ranking mob defection ever at the time, a move that would’ve pleased Lieutenant Petrosino to no end.