The art world is conflicted about political art. Most of the time, it’s considered beyond the pale, of no interest either as art or as political advocacy. On the other hand, some political art is praised just a little too much, as if making high-brow blue-chip political art were in itself a substitute for actual politics.

The Lower Manhattan Cultural Council’s "A Knock at the Door," Sept. 8-Oct. 1, 2005, curated by Seth Cameron, is a kind of Rorschach test for contemporary political art. The exhibition was famous in advance because of furious denunciations from the New York Post and the Daily News, both of which condemned the show’s politics and taste even before seeing the works on display.

Against this, the New York Times mustered an even-tempered defense, affirming the show’s right to exist and finding that many of its works were "crude and obvious" while others had some "artistic resonance."

True, the exhibition does have its problems, especially since any sense of esthetic unity was tossed in favor of an overriding political theme -- the intention of the show is to round-up art that in some way has run up against legal issues related to the U.S.A. Patriot Act. The sense of political urgency often overwhelms the artistry in many of the works. But maybe this is the idea: By framing itself as a sort of an "Entarte Kunst" for our time, "A Knock at the Door" provides a space to illustrate the effect that worries about civil liberties have on art practice.

A nihilistic attitude to esthetic values even extends to the show’s exhibition spaces, or so it seems. One half of the works are on display in what is essentially a hallway outside Cooper Union’s Great Hall, while the remainder of the show is in the South Street Seaport Museum’s obscure Melville Gallery, next to a room full of naval dioramas. Both spaces are chaotic and crowded, offering only partial and sometimes downright baffling explanatory texts.

The impression that all this gives is the chaos of an explosion of pent-up tension, the return of the passion that is repressed by the norms of cool-headed, neutralizing critical judgment. And the show is correspondingly fragmented in content.

"Knock" contains urgent, almost journalistic works, like those by Visible, an art collective directed by filmmaker Naeem Mohaiemen. Visible’s contributions to the exhibition, part of their ongoing "Disappeared in America" series (www.disappearedinamerica.org), include banners bearing dignified portraits of Muslims who have faced unjustified persecution, as well as a timeline of legal injustices perpetrated against innocent people since the Patriot Act -- the best rejoinder to those who wanted to shout down the show.

Other works in the exhibition are sleek and avant-garde, and make almost no political point at all, such as Tom Sachs’ Applied Cultural Prosthetics, two small speakers flanking a walkie-talkie, sitting on a small platform made from a section of a police barrier. The speakers broadcast snippets of conversations from security and law enforcement personnel into the gallery, nicely producing an effect of paranoia.

There are artistic statements on issues that have nothing to do with the purported impulse behind the show -- art in the age of the Patriot Act -- like Richard Serra’s eight bullet-points responding to the destruction of his Tilted Arc from 1989.

And there are works that are clearly first of all expressions of righteous indignation, raspberries of frustration at bad political times. These include Lisa Charde’s straitjacket made from an American flag, Nora Ligorano and Marshall Reese’s mug shot images of the George W. Bush, Dick Cheney and the rest of the Bush Administration, and Chris Savido’s Bush Monkeys, a portrait of George W.’s famously simian face done as a landscape of cavorting monkeys.

Overall, the show is a fraught, chaotic vortex, with no clear way through. The curator highlights this sense in a rambling essay that accompanies the show. Written in a broken, first-person style, it meanders from an account of his own encounters with the law (regarding a World Trade Center-related art project) to his discovery of how to masturbate.

The feeling of a mind reeling, gripping around for some kind of response, is the point. Because, on the one hand, it is true that art, ideally, should be free to say whatever it wants and not be subordinated to crude political demands. But on the other, it’s also true that, in the here and now, since artists make free expression their business, they have to respond in some kind of way to increasing attacks on freedom of expression.

"A Knock at the Door" doesn’t try to smooth over this conundrum, but leaves it exposed like a sensitive cavity. This is what is most interesting about the show. Its very crudeness serves as a forceful reminder that political action is necessary to art, but can’t be accomplished by art alone.

BEN DAVIS is associate editor of Artnet Magazine.