Long Island, that strange place jutting east from New York City for 100 miles, was once the very symbol of America’s postwar future, of youth and growth, and is now the opposite of that. It is an old suburb that ran out of places to sprawl, was badly hit by recession a decade ago and again in the latest downturn, and is feeling its age.  Many of Long Island’s leaders have warned that it is heading steadily down a long, slow road to ruin. It needs more jobs, cheaper housing, better transit, economic engines to replace the ones that sputtered out. It needs its vitality back.  These were the heavy bass notes of what was generally an upbeat meeting of influential Long Islanders on Tuesday at Molloy College in Rockville Centre. It was sponsored by the Long Island Index, a nonprofit organization that issues annual reports on ways the Island can better itself. This year’s report was on mass transit, specifically increasing the capacity and usefulness of the Long Island Rail Road, the sprawling passenger network that hasn’t grown significantly in, oh, a century and a half.  Walt Whitman, Long Island’s most famous son, was still a nobody in Brooklyn when the L.I.R.R. completed its main line across the Island in 1844. The village at the eastern end, Greenport, was heavily into shipbuilding and whaling. A lot has changed since then, notably the growth of the island’s population to 2.8 million. But one part of the island — a troublesome, 10-mile section of the L.I.R.R. between Floral Park and Hicksville in Nassau County — still lives in the 19th century. It has two tracks, and only two, making it a perennial cause of congestion and delays. Five of the railroad’s branch lines — and 41 percent of its ridership — converge there. This bottleneck can be a disaster in bad weather; it also keeps the railroad from sending more trains east from Penn Station, against the regular commuter flow, out to where many jobs are, or could be.  The L.I.R.R. wants to add a third track along this 10-mile stretch to shorten commutes, reduce car traffic and take a significant step toward a transit-oriented renaissance. It’s an incredibly simple solution, in theory. But in Nassau, the third track is a third rail, stymied by ferocious not-in-my-backyard protesters who have frightened lawmakers into mumbling inaction.  It’s an old story on Long Island: When an ambitious project seeks to alter the status quo for the greater good, the Nimby beast rises to kill it. At a workshop on Tuesday, various participants — including a village mayor, a city manager, town planners and academics — agreed that Long Island has plenty going for it: proximity to the city, world-class research laboratories, an educated work force, great schools and excellent beaches.  But they seemed close to despair about defeating the Nimby crowd. Jim Morgo, a former deputy county executive of Suffolk, said advocates could “infiltrate” civic and neighborhood groups, but what the project most needed was “really strong leadership from the top. You need courage from the executive and the Legislature.” You need, as one participant — a mayor himself — put it, the willingness to lose an election.  So far we haven’t seen any elected leaders go to the mat for the third track. It would be great if Gov. Andrew Cuomo did. One voice I missed Tuesday was that of a former Nassau County executive, Thomas Suozzi, now a lawyer in private practice, and an early and brilliant booster for building higher-density downtown centers near mass-transit lines to create the jobs and tax base to help support the rest of traditional suburbia.  Long Island as we knew it doesn’t work anymore, Mr. Suozzi used to say, as he called for a “New Suburbia.” What’s sad is that so many people are content with the old one.
What is it going to take for a new generation of leaders to come up with a plan to bring this sprawling stretch of suburbia out of the 19th century?