About a year and a half ago, as the Tea Party began to dominate headlines and cable-news chyrons, liberals were befuddled. This "movement" had seemingly come from nowhere. Slowly, a general-consensus explanation emerged: A few tiny conservative gatherings were trumpeted (and trumped up) by right-wing media until they had the appearance of scale. We still, however, had a hard time wrapping our heads around how big and widespread these gatherings really were. When Glenn Beck and Sarah Palin called the Tea Partiers to the National Mall this summer -- but stopped just short of calling it a Tea Party -- liberals couldn't look away.

For me, going home for the holidays every year is a reminder of the limits of rational political discourse. It's not that I descend into arguments with my family -- which is, on the whole, much more conservative than I am -- it's that we've long since learned to not even bother. We're coming from such different places, armed with totally different sets of facts, that arguing is pointless. They say that the health-care reform bill is too expensive. I point out that Republicans' proposed repeals will actually increase the deficit. They say that's not true. And we're back to square one. Best for all of us if we just tuck into the mashed potatoes and make friendly small talk.