Earlier this week Washington, DC mayor Vincent Gray announced a bold sustainability vision that is as comprehensive and ambitious in its aspirations as any in the country and, frankly, worthy of comparison to those for other cities around the world . If successful, the 20-year program contemplated by Sustainable DC will bring the benefits of green living to traditionally underserved neighborhoods, cut obesity, substantially increase the presence of nature in the city, grow jobs, dramatically cut energy use and carbon emissions, and much more. If you’re not on board with these goals, then you just don’t care much about the urban environment. In the US, the west coast cities of Seattle, Portland, and San Francisco have long led the way when it comes to environmental thinking and ambition. More recently, Chicago, New York and especially Philadelphia have produced seriously impressive plans and programs. I’ve even applauded terrifi...