Sure, Election Day 2009 will scare moderate Democrats and make passage of Obamacare more difficult. Sure, it makes it easier for resurgent Republicans to raise money and recruit candidates for 2010. But the most important effect of Tuesday’s elections is historical. It demolishes the great realignment myth of 2008.

In the aftermath of last year’s Obama sweep, we heard endlessly about its fundamental, revolutionary, transformational nature. How it was ushering in an FDR-like realignment for the 21st century in which new demographics — most prominently, rising minorities and the young — would bury the GOP far into the future. One book proclaimed “The Death of Conservativism,” while the more modest merely predicted the terminal decline of the Republican party into a regional party of the Deep South or a rump party of marginalized angry white men.

This was all ridiculous from the beginning. 2008 was a historical anomaly. A uniquely charismatic candidate was running at a time of deep war-weariness, with an intensely unpopular Republican president, against a politically incompetent opponent, amid the greatest financial collapse since the Great Depression. And still he won by only 7 points.