The role of a public intellectual in a democracy is not one that is easily understood or described. In our contemporary media culture in which celebrity is measured solely by notoriety rather than the force of a person's ideas, it is difficult to imagine how a person such as Irving Kristol can be properly appreciated. Kristol, who died last week on the eve of Rosh Hashana at 89, was not that well known outside of the realm of intellectual life. He didn't write best-selling books or edit mass circulation magazines. In fact, the number of his fellow Americans who actually read anything he had written was probably relatively small, certainly far fewer than the many millions who watch his famous son William (who is himself a formidable intellectual voice and the editor of the Weekly Standard magazine), speak on network television about the issues of the day. But the reach of Kristol's ideas can be seen not only in his role in the creation of an important intellectual movement - neoconservatism - of which he was said to be the godfather, but in the way his critiques of liberalism irrevocably changed the national political conversation. Like many another child of Jewish immigrants who came of age during the Great Depression, he was a socialist during his youth and a liberal as a young man. But unlike so many people who start out in one place and then spend the rest of their lives trying to prove, against the force of events and reason, that what they originally thought was always right, Kristol's keen mind would not let him stand still as history moved past the era of the New Deal. Kristol is best remembered for his definition of a neoconservative as a liberal who "had been mugged by reality." But there was more to this than just a quip. He turned an informed eye and an inquisitive, creative mind on the problems of his era and the ideological patent nostrums that were peddled to solve them, and responded with withering analysis and cogent thought. The result was a body of thought that first rejected the Marxist beliefs of his youth and then the flabby liberalism that rejected the imperative to resist Soviet imperialism abroad, while being too rigid to take a rational look at the failings of the welfare state, affirmative action and the leftist counterculture. IN HIS work at publications such as Commentary, Encounter, The Public Interest and The Wall Street Journal, as well as at Basic Books and the American Enterprise Institute, he help lay the foundation for a renaissance of conservative thought. But his journey from the Left to the Right was not merely a matter of, as a more traditional conservative such as William F. Buckley said, "standing athwart the path of history and saying no." Rather, Kristol was concerned with seeing what policies worked and which did not. Not satisfied with just theorizing about the issues of the day, he went deeper than merely listing the failures of liberal social science. His response was to promote a conservatism that was founded in a positive vision of American values both in terms of an economics that embraced the growth of wealth rather than its redistribution and a patriotic embrace of the universal importance of democratic values. Unlike the lugubrious worldview of the traditional right that is often mired in pessimism about humanity, Kristol's neoconservatism was profoundly optimistic about America and the West. As Kristol himself wrote, "Neocons feel at home in today's America to a degree that more traditional conservatives do not. Though they find much to be critical about, they tend to seek intellectual guidance in the democratic wisdom of Tocqueville rather than in Tory nostalgia." As such, it is no exaggeration to say that Kristol's influence was at the heart of the conservative political revival that won several national elections in a period that stretched from Ronald Reagan to George W. Bush. In this era, rather than being the "stupid party," Republicans became the party of ideas. Neoconservatism's task was, he said, to "convert the Republican Party and American conservatism in general, against their respective wills, into a new kind conservative politics suitable to governing a modern democracy." TODAY, LIBERAL critics would like to imagine that neoconservatism's day is over. They forget that the triumphs of neoconservative thought had already altered the country's political landscape long before the term "neocon" became a leftist term of abuse, as well as a touchstone for anti-Semitic incitement on both the far left and the far right. While the vast majority of American Jews are still to be found on the Left, Kristol nevertheless must be credited, along with his fellow neocon pioneer Norman Podhoretz, with creating a lively debate about the follies of liberal orthodoxy and the perils to Jewish interests and specifically to Israel of Jews being trapped in a politics governed by knee-jerk support for any one party or ideology. Though the battle to open up Jewish minds on that subject is still very much an uphill climb, the penetrating insights of Kristol have ensured that it is one that continues to be fought. Neoconservatism continues to flourish in the formidable intellectual institutions that Kristol help build and the writers, thinkers and policy wonks deeply influenced by his thought and his example that labor in them. More importantly, his ideas helped shape the blueprints for a conservative political revival in the future. For if there is to be yet another renaissance on the Right, as there surely will, it can only be one whose character will be informed by Kristol's optimism about America, its faith, its potential and its people. May his memory be for a blessing. The writer is executive editor of Commentary magazine where he contributes to its blog Contentions at www.commentarymagazine.com.