This piece is adapted from a speech given before the Alliance for Global Sustainability last month at the Massachusetts Institute of Technology in Cambridge, Mass. The full speech -- "Reflections on Sustainability and Universities and Whether Environmentalism Has Died" -- can be found here. Are the reapers quitting too soon? The environmental community is in turmoil over "The Death of Environmentalism," the challenging essay released by Michael Shellenberger and Ted Nordhaus last fall. Their thesis is that the environmental community has "strikingly little to show" for its efforts over the last 15 years and that environmental leaders are not articulating …