All good things must come to an end. Jan. 20, 2009, marked the end of a conservative era.

Since Ronald Reagan’s election in 1980, conservatives of various sorts, and conservatisms of various stripes, have generally been in the ascendancy. And a good thing, too! Conservatives have been right more often than not  and more often than liberals  about most of the important issues of the day: about Communism and jihadism, crime and welfare, education and the family. Conservative policies have on the whole worked  insofar as any set of policies can be said to “work” in the real world. Conservatives of the Reagan-Bush-Gingrich-Bush years have a fair amount to be proud of.

They also have some regrets. They’ll have time to ponder those as liberals now take their chance to govern.

Lest conservatives be too proud, it’s worth recalling that conservatism’s rise was decisively enabled by liberalism’s weakness. That weakness was manifested by liberalism’s limp reaction to the challenge from the New Left in the 1960s, became more broadly evident during the 1970s, and culminated in the fecklessness of the Carter administration at the end of that decade.

In 1978, the Harvard political philosopher Harvey Mansfield diagnosed the malady: “From having been the aggressive doctrine of vigorous, spirited men, liberalism has become hardly more than a trembling in the presence of illiberalism. ... Who today is called a liberal for strength and confidence in defense of liberty?”