"This civil disobedience stuff kind of works. How many coal plants are there?" So wrote Bill McKibben, one of the climate movement's leading men of letters, in an email to friends and allies last Thursday. He was reacting to Nancy Pelosi and Harry Reid's joint announcement that the Capitol Power Plant-owned and operated by our U.S. Congress-would be converted from coal to natural gas. The funny thing is, the civil disobedience hadn't even happened yet. That was today.Despite Pelosi and Reid's attempts to preempt the non-violent action, an estimated 3,000 activists gathered on Capitol Hill in Washington this chilly afternoon for the Capitol Climate Action, billed as "the largest mass civil disobedience for the climate in U.S. history."Back in December, McKibben and Wendell Berry sent around a powerful letter calling for action. It began "Dear Friends, There are moments in a nation's-and a planet's-history when it may be necessary for some to break the law in order to bear witness to an evil, bring it to wider attention, and push for its correction. We think such a time has arrived." Many others agreed-James Hansen, Gus Speth, Martin Sheen, Noam Chomsky, Paul Hawken, Naomi Klein, and thousands of others endorsed the action.It's hard to see the Capitol Climate Action as anything short of a huge victory for clean air and a livable planet. The threat of the action was enough to ensure that targeted plant will stop burning coal. The plant was effectively shut down for hour hours this afternoon, all five entrances blockaded by peaceful protesters. The message seems to have been heard far and wide, through old media and new. (I saw it twice featured on CNN, and #climateaction was the leading "twitter trend" for most of the afternoon.) And, as of this report, there have been exactly zero arrests. The cops were cordial to the well-organized crowd (many of whom had sat through non-violence and civil disobedience training this morning), and the day will be remembered not for radical protest, but for the peaceful delivery of a critical message.