Truth and politics have always been rather curiously intertwined, but in a democratic state they are especially so: the truth becomes a political ideal even as it remains, at most, a political instrument. The result is both a populus and a press which are left to grapple constantly with political facts that never quite seem to matter as much as they should.

I was reminded of this again over the weekend, when I encountered two works that either noted or tried to account for an absence of political truth. The first was a superb commencement speech delivered this year at Berkeley by Mark Danner, who mentioned -- albeit largely in passing -- that "never in my experience has frank mendacity so dominated our public life." The second came from yesterday's Times Magazine cover-story on torture, in which Joseph Lelyveld writes that

An implicit understanding has been reached, or so I would argue, between the governed and those who govern: that the prime task is the prevention of future attacks on our own soil as opposed to the punishment of past attacks; that extralegal excesses, not excluding kidnappings and physical abuse, may be necessary in the effort to suppress terrorists seeking to implant sleeper cells in our midst and equip them with deathly substances and bombs; that in pursuit of this goal, much can be forgiven, including big mistakes (the abuse and indefinite detention of innocent people, the tacit annulment -- for foreigners, anyway -- of legal guarantees, not to mention a costly war of dubious relation to the larger struggle); and that the less we know as a people about our secret counterterrorism struggles and strategies, the less we contemplate the possibly ugly consequences, the easier it will be for those in authority to get on with the job of protecting us.

As the story on torture implies, our principal political concern is not with truth but security. The American public is willing to cede its concern with truth provided that either the resultant ignorance or mendacity ensure its safety.

Yet this can only ever be a short-term mandate, and one, furthermore, that must be restricted to a military or investigative sphere. The reason has to do with the proper function of political truth in a democratic society: namely, to foster trust between public representatives and the public itself. Propagate ignorance or dishonesty for too long or in too many ways, and eventually you will erode the public trust in your ability to govern, regardless of whether or not you provided the requisite security.

At present, Bush has expanded the sphere of what might be termed "acceptable prevarication" well beyond its "acceptable" limit. As the Clooney affair demonstrates, mendacity is now a part of his administration's general modus operandi rather than one specific to security concerns only. It may not show now, but in time this will catch up to him: he is eroding not the trust in his performance, but the very possibility of such trust.

Call me an optimist, but I have an abiding faith that that will, in fact, prove his downfall.