Greenpeace protests the obstruction of the United State's first offshore wind farm on the waters of Nantucket Sound. The four-year-old battle started heating up last summer when Greenpeace USA staged a demonstration against well-known eco-activist Robert F. Kennedy Jr., who's been an outspoken opponent of the proposal for a 130-turbine wind-power project in Horseshoe Shoal, a shallow portion of Nantucket Sound south of Cape Cod. Kennedy -- a senior attorney at Natural Resources Defence Council and a pioneer in the waterway-protection movement -- was on a sailboat for an event with the Alliance to Protect Nantucket Sound, which opposes the wind project. A Greenpeace vessel cruised up alongside with a banner that read, "Bobby, you're on the wrong boat" -- an action that was part of a larger Greenpeace campaign pressuring Kennedy to change his mind on the development.