AP Photo

There is plenty of blame to share for the political demise of climate change legislation in Washington. Timid Democrats, obstinate Republicans, a risk-averse White House and a sour public outlook that green groups couldn't counter. Each played a role.

Following a health care fight, a $1 trillion stimulus package and new financial regulations, there was neither the will nor patience for another major showdown. The doomed plan was built on the much-mocked cap and trade approach that set limits on carbon emissions (think mainly coal-fired power plants) and allowed polluters to buy and sell credits to stay within the caps.