Krugman on building a green economy

"there is widespread agreement among environmental economists that a market-based program to deal with the threat of climate change — one that limits carbon emissions by putting a price on them — can achieve large results at modest, though not trivial, cost. There is, however, much less agreement on how fast we should move, whether major conservation efforts should start almost immediately or be gradually increased over the course of many decades. "
http://www.nytimes.com/2010/04/11/magazine/11Economy-t.html