The big news in conservative circles today is that Jim DeMint will be leaving the Senate to run the Heritage Foundation, built from scratch by its innovative founder, Ed Feulner, into a colossus that redefined the way public-policy ideas could be integrated into the ongoing political process on Capitol Hill. Before Heritage was created in 1974, Capitol Hill was a vast wasteland intellectually and ideologically, especially on the Republican side; most policy was generated by the bureaucrats in the executive branch and then refined into legislative form by permanent staff on the Hill. Heritage began examining specific pieces of legislation and offering criticisms of them and proposals for their refinement, as well as producing short and coherent documents on a range of issues to educate congressmen and their staffs about the effects their votes could and would produce. This is now standard practice across the ideological camps in D.C., but it was entirely new and enormously influential.

Heritage is commonly called a “think tank,” but it’s something far more complex than that—it is one of the largest grass-roots organizations in the world, with an astonishing 700,000-plus donors and supporters and a budget of $75 million. And like most of the right, it has found itself see-sawing between trying to offer constructive policy advice advancing innovative legislation and standing in potent opposition to liberal innovations.

The temptation for DeMint will be to stress the institution’s role in opposition, which is his stock in trade as a senator, and to downgrade its policy role, which has had its major “up”s (welfare reform) and its blind-spot “down”s (advocating a health-care mandate in 1994). But if ideas do not play the central role, Heritage will hollow itself out, and that would be a great shame. Ed Feulner stands as one of the great public-policy innovators of the 20th century; it would be thrilling if the same could be said of Jim DeMint when he passes on the mantle to his successor.