Borat Sagdiyev is one of several characters that Sacha Baron Cohen created for his comedy sketch-show Da Ali G Show. Viewers of that programme will be familiar with his cheap grey suit, malapropisms and casual bigotry. In 2000 Baron Cohen introduced Ali G to the big screen with Ali G In Da House (in which the white-suburban-wannabe-black-ghetto-boy becomes an MP). Now, it's Borat's turn for a movie.

As the subtitle (Cultural Learnings Of America For Make Benefit Glorious Nation Of Kazakhstan) suggests, the film takes the ostensible form of a mock-documentary for Kazakh TV, following on from Borat's "guides" to Britain and the USA in the sketch show. This is essentially more of the same, but in making the shift to feature-length movie, Baron Cohen and his co-writers have introduced a plot. Cultural Learnings is also a quest movie. Borat travels to America, falls in love with a magazine image of Pamela Anderson, the pneumatic embodiment of the American dream, and crosses the country to make her his bride. The journey provides the material for Borat's documentary (and Baron Cohen's satire), but the quest itself becomes something more than a mere framing device. In some ways, its presence interferes with the satirical possibilities offered by the sketch format.

The film begins and ends in Kuczek, Kazakhstan, a ramshackle peasant village, with donkeys and pigs in its living rooms, and the Running of the Jew as its light entertainment. Women are prostitutes, men rapists and the children carry rifles, but everyone seems jolly and happy. Borat decides to go to America to find solutions to the country's problems - "economic, social and Jew".

Borat's "cultural learnings"

Much of the (ticket-selling) attention surrounding the film's release has focused on the Kazakhstan government's concern that the country is unfairly maligned. (This is despite a disclaimer asserting that "nothing in this film is intended to convey the actual beliefs, practices or behaviour of anyone associated with Kazakhstan.")

On 27 September, coinciding with President Nursultan Nazarbayev's visit to Washington and therefore supposedly nothing to do with the film, the government took out a four-page advertisement in the New York Times and International Herald Tribune featuring thirteen short articles commenting on its oil reserves, fast economic growth, and "one of the hallmarks of the nation", its "religious tolerance". But what of satirical tolerance?

Last year Nurlan Isin, president of the Association of Kazakh IT Companies, intervened to stop Borat "badmouth Kazakhstan under the .kz domain name." Shortly afterwards, however, President Nazarbayev's daughter Dariga admitted that the website (which simply moved to www.borat.tv ) had "damaged our image much less than its closure."

Perhaps the chief "cultural learning" of the Borat experience is that all publicity is good publicity. Both the "glorious nation" of Kazakhstan and the not famously liberal Fox Film Corporation have made considerable 'benefit'. In an article in the London Times, Erlan Idrissov, the Kazakh ambassador to Britain, again promoted the warmth and hospitality of his country (and the fact that a new synagogue had been built in Astana), but this time he also acknowledged that Kazakhstan was benefiting from "the kind of media attention of which previously [I] could only dream." Meanwhile, against all predictions, Borat was the number one movie in the States in its opening weekend (3-5 November), grossing $26.4 million.

Clearly Baron Cohen was not motivated by a desire either to denigrate or promote Kazakhstan. The country of the movie (filmed in Moroieni, Romania) is a fictional mishmash of eastern European (more than Asian) clichés. Borat and his sidekick Azamut (Ken Davitian) speak a mixture of Polish, Czech, Russian, Armenian and Hebrew (particularly funny for mimicking anti-semites). The assumed primitivism of the east is only the secondary object of Baron Cohen's satire. More importantly, Borat is an ignoble savage who will reveal a savagery concealed beneath the affable surface of the United States.

The comedy of shock

Some of the jokes present him as a Chaplinesque Innocent Abroad (mistaking the elevator for his hotel room), while others get laughs at his inability to follow simple social rules - for example, that one should not defecate on the grass in front of Trump Towers or masturbate in front of a Victoria's Secret store. Yet of course the joke has an edge - what, one might one ask, is the purpose of Victoria's Secret if not to inspire masturbation?

Another kind of joke suggests that Borat's values (boorishness, misogyny, anti-Semitism) are shared by the country he travels through - or, at least the Southern States in which he spends most of his time. Surely Borat has reached the heart of darkness when just after Mississippi Supreme Court Chief Justice Jim Smith denounces evolution, he is encouraged to speak in tongues at a Pentecostal prayer meeting?

Before this, Borat encounters a salesman whom he asks to fit a "pussy magnet" into his car and another from whom he demands the best gun for shooting Jews (a.k.a. shape shifters). Both offer to help without blinking an eye. But it's not only men keen to make a dollar who refuse to challenge Borat. Most of the people he meets go out of their way to be friendly to him, simply accepting his behaviour as well as his prejudices as foreign, and eager to help him assimilate. (The only real exception is an organisation called the Veteran Feminists of America who cut to the chase with admirable speed.)

The American desire not to make waves (up to a point) is made most clear when Borat attends a fancy, all-white dinner party in Birmingham, Alabama. Borat is extremely rude: he tells one woman she is ugly and assures another that she is lucky that her husband (whom he is convinced is a "retard" instead of "retired") is allowed out - but the hospitable Southerners maintain their manners. "It wouldn't take much for him to be Americanised", the hostess says. Moments later Borat returns to the dinner table from a trip to the toilet with a little bag full of shit. Now, you think, they'll surely change their minds, but no. Instead, the hostess calmly takes him back to the bathroom and explains about flushes and toilet paper. Is there nothing these people won't tolerate? Of course there is. The doorbell rings and a large black woman in a tiny skirt arrives (Borat has summoned a prostitute as his guest). The couple are thrown out of the house. Her presence, not his, has exposed them.

The fine line between acceptable and not acceptable is also what makes Borat's visit to a Texan rodeo so devastating. He praises the "War of Terror" to large cheers, and gets an only slightly less warm response when he urges George Bush to drink the blood of every man, woman and child in Iraq. Finally, when he sings the Kazakh national anthem (mainly about potassium production) to the tune of The Star-Spangled Banner, we see members of the audience looking at each other uneasily. A cowgirl loses her concentration and falls off her horse. At what point has Borat crossed the line?

The Guardian critic Peter Bradshaw suggests that the fascination of the film lies in the fact that Borat himself is "so horrible, with a deplorable quality mitigated only by his ineffectuality." I would argue the opposite - that the narrative (partly deliberately; partly unavoidably) works to make him sympathetic. This happens, I think, in two ways. The first is through the movie's physical humour, in particular the extended naked wrestling scene between Borat and the obese Azamut, which starts in a Dallas hotel room and ends up in a meeting room full of mortgage brokers. I saw the film in a cinema full of sixteen-year-olds and this scene got the biggest laugh. For all the movie's satire of frat-boys, this is deliberate frat-boy humour, letting everyone off the hook for a few minutes.

But while this scene provides temporary relief from Borat's horribleness, the narrative supplies a more sustained solution. Following the Alabama dinner party, Borat goes out on the town with the prostitute Luenell and walks her home in the moonlight. She's brought out a side of him that we haven't seen yet: the gentleman. Eventually he realises that it is Luenell (and not Pamela Anderson) whom he loves, and in the final scene, they are married and living in Kuczek. Even the village seems to be transformed a little. The Running of the Jew, for example, has been abandoned for much milder Christian-baiting.

Despite the seeming ubiquity of Borat's prejudices (homosexuals, gypsies, women, Jews), he, and his countrymen, seem to have no problem with blacks. There is a scene early on when Borat calls Alan Keyes (a conservative Republican in the Reagan administration) a "genuine chocolate face", but the remark seems to be there to make his bigotry seem comprehensive. Elsewhere Borat is shown to get on better with blacks than anyone else (whether hanging out and learning to speak like a group of kids in Atlanta) or riding a bucking bronco with Luenell. She's good for a laugh in a Kazakh kind of way and that's why she fits in so well back in the village. But is that such a compliment?