Some of the best-known think tanks are true to the original, independent model typified by the venerable Brookings Institution. The new breed is different. 'Disguising themselves as think tanks, a new wave of conservative political reformers has galloped onto the scene and is shooting fountains of misinformation, twisting facts to serve their purposes and making no effort whatsoever at giving an impartial look at reality,' writes journalist Melissa Rossi in her new book, What Every American Should Know About Who's Really Running the World (Plume, 2005).

The 1973 birth of the Heritage Foundation, funded in large part by Pennsylvania billionaire Richard Mellon Scaife, ushered in the era. Eschewing independent fact-based research, Rossi says, Heritage pumps out a steady stream of biased 'pseudo-reports' that read like ad campaigns. The foundation 'wielded such formidable political-religious muscle during the Reagan administration that some considered [it] to be a shadow government.'

Since then, Scaife and other conservatives, including the Coors, Olin, Bradley, and Koch foundations, have pumped hundreds of millions of dollars into policy factories that generate media-friendly reports, op-eds, and TV talking points on conservative causes.

Some of these think tanks, like Heritage, focus on a religion-based cultural agenda, but most tend to focus on the narrow interests of their largest sources of cash: corporations. Pushing a corporate agenda of lower taxes and less government regulation, the powerhouses of the business right include such think tanks as the American Enterprise Institute, Cato Institute, Competitive Enterprise Institute, and Hudson Institute. Still others, like the Center for Security Policy, focus on defense issues and are funded largely by military contractors.

This rightward creep has even affected old-line think tanks like the Brookings Institution and the Center for Strategic and International Studies, where a number of neoconservative scholars took desks before the Iraq war.

In the past few years, unions and progressive philanthropists, like investors George Soros and Andy Rappaport, have funded left-wing tanks -- groups like the Center for American Progress, Economic Policy Institute, and Media Matters for America.

This balancing of the scales is not good, in Rossi's view, because 'the emergence of these well-funded ideological institutions on the political scene is co-opting the collective cerebral establishment.' In other words, ideologically driven research is the problem, not the solution. 'More than ever,' she says, 'we're watching the slow death of the true think tank and with it any semblance of impartial, objective thought.'