Just at the moment when you might have lamented the absence of politics in the arts, outside the revived documentary field, along comes Nicholson Baker with Checkpoint, a book that has outraged many with its reflection of the rage and divisions in current day America.

The slim book (115 pages in total) is more of a one-act play than anything, consisting of a dialogue between two old friends in a hotel room, one of whom insists that he is going to assassinate President George W. Bush. It’s a rare thing for a piece of fiction to address current affairs in the white heat of the moment, such as this book does. The pages are littered with references to events that have just recently been seen worldwide, be it the murder of civilians at a checkpoint in Iraq or the human rights abuses at Abu Ghraib prison. It’s been accused of sensationalism, precisely because of its immediacy and its central premise of an enraged everyman determined to eliminate “this unelected fucking drunken OILMAN”. Certainly Nicholson Baker is no stranger to controversy, having written two literary hardcore erotic novellas, one of which Vox, as the Starr Report helpfully pointed out, was given as a present to Bill Clinton, by Monica Lewinsky.

There are two very separate arguments to be made in relation to the book. The first is how wise/acceptable is it to write or publish a book like this, at a time when tensions are running as high as they have ever between different political poles in America? The Christian Science Monitor questioned how legal a work like this may be, but as a work of fiction it is protected by the Supreme Court’s defence of Freedom of Speech. The implications for Mr Baker, and for freedom of speech in general, if something, God forbid, were to happen to President Bush, are worrying.

The second argument – in a sense clarifying the first – questions whether it is a worthy piece of fiction? How well is it written? Is it just a cheap shot of sensationalism, cashing in on the mood of the country, or are there serious themes present?

For such a slim book, it has a remarkable amount going on in it. It’s an impressive literary creation, firstly in the sense that the characters come off the page. The story is all dialogue, and at very few passes does it fail to ring true, a notoriously difficult feat. The one concession to driving the story forward, at the expense of the dialogue is that in a number of passages, Jay, the would be assassin, rants on for two or three paragraphs without interruption, stating his case. In a real conversation it’s unlikely or next to impossible. The rhythm of the conversation is riveting though, ranging from belligerent politics, through to discussions on how ugly Wal-Mart stores are. The pace is handled deftly, and at the end there’s the feeling that you’ve been listening with your ear to the wall from the next room – a not entirely morally re-assuring position. Indeed, there are many similarities to the position of the reader, and that of Ben, who has been tricked into being a witness to Jay’s crazy plan, and in that sense an accessory. Much of this book hinges on making the reader uncomfortable and collusive.

As to the critics who have berated Baker for encouraging assassination of the President, the first defence would have to be how clearly he outlines the unhinged paranoia of Jay. Jay is a character for whom one feels sympathy, rather than empathy. He’s clearly unstable, having had mental and emotional problems that are constantly obliquely referred to. His plan itself, to shoot the President with guided bullets, that have been marinating in a tin with a printed photo of George W. is patently ludicrous.

Baker stated in interview “It is an attempt to put a moral moment under the magnifying glass. Our political beliefs are seldom consistent: that’s one reason why fiction, which tolerates imprecision and inconsistency – in fact, revels in it – can do a better job than non-fiction can of capturing the mixed-up feeling of being bystanders to a war”.

Checkpoint is, in the final reckoning, a brave and complex book that provokes questions and debate. As always, read the thing before joining the polemic.