Abandoned neighborhoods. Boarded-up harbor facilities. An oil refinery submerged under several feet of brackish water. The Statue of Liberty slowly sinking into the sea. "Rising Currents: Projects for New York's Waterfront," a new show at the Museum of Modern Art, reflects a level of apocalyptic thinking about this city that we haven't seen since it was at the edge of financial collapse in the 1970s, a time when muggers roamed freely, and graffiti covered everything.