It's been a long year--Barack Obama has faced, in rough order, John McCain, global financial collapse, Mahmoud Ahmadinejad, the Blue Dogs, the Progressive Caucus, the Gang of Six, Glenn Beck, Representative Joe Wilson (R-Hissy), and the third of Republicans convinced he was born somewhere else. Of course, minus the birth certificates, roughly the same has been true for Hu Jintao and Nicolas Sarkozy, for Angela Merkel and Manmohan Singh. That's what politics is--a series of challenges, which are rarely won or lost completely. You get part of what you wanted (everyone with health insurance), and maybe you leave other stuff for another day (the public option). That's why we call politics the pursuit of the possible.

On a hot spring evening in early May--the kind that elicits nervous global-warming jokes--a crowd of powerful and wealthy people are gathered at a cocktail party in the banquet hall in the Hart Senate Office building on Capitol Hill, sipping wine and talking carbon.