The passing of Irving Kristol last month at the age of 89 coincided with the death, at a much younger age, of the intellectually serious conservatism he did so much to foster. As a liberal who was fond of both, I've been feeling the loss. (Click here to follow Jacob Weisberg)

In the heyday of Kristol's influence in the 1980s, Republicans styled themselves the party of ideas. Whatever you thought of those ideas—challenging Soviet power, cutting taxes, passing power back to the states, cutting welfare for the undeserving poor—they represented a coherent attempt to remodel government around a conservative vision. Today, as during the preconservative stage of Kristol's career in the 1950s, the Republican Party takes itself much more lightly. It has fallen back upon what Lionel Trilling once called "irritable mental gestures"—crankily rejecting liberal attempts to come to grips with the country's problems without offering any plausible alternative. Since the last election, it has been the brain-dead home of tea parties, pro-life amendments, and climate-change denial.

Those on the right frustrated with the paltry politics of today's GOP may find some inspiration looking back at Kristol's best work, which was done in the late 1960s and 1970s when he was hovering somewhere between left and right. With his friend Daniel Bell, Kristol in 1965 founded The Public Interest, one of the really important American political magazines, and went on to edit it for the next 40 years. The circle around The Public Interest was composed of liberals disturbed by the drift of then-regnant liberalism. Kristol and his colleagues accepted FDR's New Deal as both a political reality and a minimum stand-ard for an advanced society, but worried that the movement toward value-free social policy was undermining it. They wanted to fix government, not break it further.

As that skepticism about Democratic policies deepened, the socialist writer Michael Harrington dubbed the tendency neoconservatism. A brilliant publicist, Kristol claimed the slur as a badge of honor and sought to define it as a political philosophy. "Neo-conservatism is not at all hostile to the idea of the welfare state, but it is critical of the Great Society version of the welfare state," Kristol wrote in 1976 (in NEWSWEEK). His well-known formulation was that a neoconservative is a "liberal who has been mugged by reality." But the goal of the neoconservatives—in those days, principally focused on domestic rather than foreign policy—remained better government, more mindful of tradition and respectful of the values of the people.

How did this prudent outlook devolve into the spectacle of ostensibly intelligent people cheering on Sarah Palin? Through the 1980s, the neoconservatives became more focused on political power and less interested in policy. They developed their own corrupting welfare state, doling out sinecures and patronage subsidized by the Olin, Scaife, and Bradley foundations. Alliances with the religious right skewed their perspective on a range of topics. They went a little crazy hating on liberals. Over time, their best qualities—-skepticism about government's ability to transform societies and rigorous -empiricism—fell by the wayside. In later years, you might say Kristol and the neoconservatives got mugged by ideology. Actually, they were the muggers. "It becomes clear that, in our time, a non--ideological politics cannot survive the relentless onslaught of ideological politics," Kristol wrote in 1980. "For better or for worse, ideology is now the vital element of organized political action."

There was no clearer sign of the shift than the effort by Kristol's son, William, to prevent health-care-reform legislation from passing in 1993—on the grounds that the political benefit would accrue to Bill Clinton. Today, that sort of Carthaginian politics has infected the entire congressional wing of the GOP, which equates problem solving with treasonous collaboration. Though President Obama has tried to compromise with them in crafting the last missing piece of the social--insurance puzzle, even allegedly moderate Republicans are not interested in making the legislation more conservative. They are only interested in handing Obama a political defeat.

This is no good at all. Without a substantive challenge, liberals grow smug and lazy. They overreach and overspend. Conservatives need to return to civic responsibility, not just to check their opponents but to offer the country a real choice. They need some new neoconservatives. They need the old Irving Kristol.

Jacob Weisberg is also the author of The Bush Tragedy and In an Uncertain World: Tough Choices from Wall Street to Washington .

© 2009