Why are so many films so bad? This year's Oscar nominations are a parade of propaganda, stereotypes and downright dishonesty. The dominant theme is as old as Hollywood: America's divine right to invade other societies, steal their history and occupy our memory. When will directors and writers behave like artists and not pimps for a world-view devoted to control and destruction?

I grew up on the movie myth of the Wild West, which was harmless enough unless you happened to be a Native American. The formula is unchanged. Self-regarding distortions present the nobility of the American colonial aggressor as a cover for massacre, from the Philippines to Iraq. I only fully understood the power of the con when I was sent to Vietnam as a war reporter. The Vietnamese were "gooks" and "Indians", whose industrial murder was preordained in John Wayne movies and left to Hollywood to glamourise or redeem.

I use the word murder advisedly, because what Hollywood does brilliantly is suppress the truth about America's assaults. These are not wars, but the export of a gun-addicted, homicidal "culture". And when the notion of psychopaths as heroes wears thin, the bloodbath becomes an "American tragedy" with a soundtrack of pure angst.

American airbrush

Kathryn Bigelow's The Hurt Locker is in this tradition. A favourite for multiple Oscars, her film is "better than any documentary I've seen on the Iraq war. It's so real it's scary" (Paul Chambers, CNN). Peter Bradshaw in the Guardian reckons it has "unpretentious clarity" and is "about the long and painful endgame in Iraq", and that it "says more about the agony and wrong and tragedy of war than all those earnest well-meaning movies".

What nonsense. This film offers a vicarious thrill through yet another standard-issue psychopath, high on violence in somebody else's country where the deaths of a million people are consigned to cinematic oblivion. The hype around Bigelow is that she may be the first woman to win the Oscar for Best Director. How insulting that a woman is celebrated for a typically violent all-male war movie.

The accolades echo those for The Deer Hunter (1978), which critics acclaimed as "the film that could purge a nation's guilt"! The Deer Hunter lauded those who had caused the deaths of more than three million Vietnamese, while reducing those who resisted to barbaric commie stick figures. In 2001, Ridley Scott's Black Hawk Down provided a similar, if less subtle, catharsis for another "noble failure" by the US, this time in Somalia, airbrushing the heroes' massacre of up to 10,000 Somalis.

By contrast, the fate of an admirable American war film, Redacted, is instructive. Made in 2007 by Brian De Palma, the film is based on the true story of the gang rape of an Iraqi teenager and the murder of her family by US soldiers. There is no heroism, no purgative. The murderers are murderers, and De Palma ingeniously describes the complicity of Hollywood and the media in the epic crime of Iraq. The film ends with a series of photographs of Iraqi civilians who were killed. When it was ordered that their faces be blacked out "for legal reasons", De Palma said: "I think that's terrible because now we have not even given the dignity of faces to this suffering people. The great irony about Redacted is that it was redacted." After a limited release in the US, the film all but vanished.

Non-American (or non-western) humanity is not deemed to have box-office appeal, dead or alive. They are the "other" who are allowed, at best, to be saved by "us". In Avatar, James Cameron's vast and violent money-printer, 3-D noble savages known as the Na'vi need a good-guy American soldier, Sergeant Jake Sully, to save them. This confirms they are "good". Natch.

My Oscar for the worst of this year's nominees goes to Invictus, Clint Eastwood's unctuous insult to the struggle against apartheid in South Africa. Based on a hagiography of Mandela by a British journalist, John Carlin, the film might have been a product of apartheid propaganda. In promoting the racist, thuggish rugby culture as a panacea of the "rainbow nation", Eastwood gives barely a hint that many black South Africans were deeply embarrassed and hurt by Mandela's embrace of the hated springbok symbol of their suffering. He airbrushes white violence - but not black violence, which is ever present as a threat. As for the Boer racists, they have hearts of gold, because they "didn't really know". The subliminal theme is all too familiar: colonialism deserves forgiveness and accommodation, never justice.

Sheer realism

At first I thought Invictus could not be taken seriously, but then I looked around the cinema at young people and others for whom the horrors of apartheid have no reference, and I understood the damage such a slick travesty does to our memory and its moral lessons. Imagine Eastwood making a happy-Sambo equivalent in America's Deep South. He would not dare.

The film most nominated for an Oscar and promoted by the critics is Up in the Air, which stars George Clooney as a man who travels the US sacking people and collecting frequent-flyer points. Before the triteness dissolves into sentimentality, every stereotype is summoned, especially of women. There is a bitch, a saint and a cheat. However, this is "a movie for our times", says the director, Jason Reitman, who boasts about having cast real sacked people.

“We interviewed them about what it was like to lose their job in this economy," said he, "then we'd fire them on camera and ask them to respond the way they did when they lost their job . . . It was an incredible experience to watch these non-actors with 100 per cent realism." Wow, what a winner.