There was at one point going to be a train that ran from Bay Ridge across the narrows. They even started on the tunnel before the Second World War and funding cuts killed it, and we got the Verrazano Narrows Bridge instead.

Staten Island really needs a northern rail line, and a rail connection into Brooklyn would be good too, but it's still a very remote place. Few people are going to want to commute two hours by train through Brooklyn into Manhattan.