"I am willing to love all mankind, except an American." - Samuel Johnson

In his irreverent book about US government, Parliament of Whores , the humorist P. J. O'Rourke, with characteristic disrespect, describes the American political system as being like fast food: "Mushy, insipid, made out of disgusting parts of things, and everybody wants some." The American political system has many people salivating - only now they're in for the kill. The Bush Administration's enthusiasm for military engagement in Iraq has galvanised past critics, created new ones and has pretty much made America the world's obsession. The critics have descended like a biblical plague of locusts. God only knows what will be left over when they've finished eating.

From the capitalism-run-riot allegories of The Godfather, Scarface and Three Kings to the conspiratorial machinations of All The President's Men and JFK, from the dippy paranoia of The X-Files and Alias to the dystopian soap opera of The Sopranos , from the desperate poor and the debased rich of Raymond Chandler to the cesspit faux-histories of James Ellroy, the world has been reared on an American pop-culture that glamorises her own moral failure. Even Bruce Springsteen's megahit anthem Born in the USA was intended as a biting indictment of the system. But you have to wonder: is dissing the system a substitute for actually doing something about it?

The intellectual father of self-detraction American style is Noam Chomsky, who famously said: "I have often thought that if a rational fascist dictatorship were to exist, then it would choose the American system." Chomsky is a renowned linguistics professor, political activist, libertarian socialist and the author of numerous best-selling books about America's evil ways. His followers - yes, there's a quasi-religious tone to his oeuvre - view the 74-year-old academic as an infallible commentator and supreme moral prophet. The Guardian newspaper recently reported that Chomsky, along with Shakespeare, Marx and the Bible, is one of the 10 most quoted sources in the humanities.

In interview, Chomsky's beliefs are compellingly articulated. His articles are succinct and readable. His books, however, are monstrously dull, fact-filled volumes with stern titles such as Deterring Democracy. His most approachable new tome is Power and Terror , a series of post-September 11 interviews. This is Chomsky on American history: "I'm sitting here because some religious fundamentalist fanatics from England came over here and started exterminating the local population, then lots of others followed them and they exterminated the rest of the population."

Chomsky's America isn't the home of the brave, it's the home of the depraved. All his works propound the same uncomplicated theses. America is an empire. Empire's violate human rights to stay in power. American capitalism is the world's great evil. Chomsky: "The War on Terror is pure hypocrisy, virtually without exception." The terrorists hate America, he says, because America herself commits terrorism - propping up dictators such as Saddam and then getting rid of them when they are no longer useful to US interests.

Chomsky's aim is to bring the horrible facts to the public in the hope that it will inspire grass-roots action. Unfortunately, he describes America in such frightening terms that you're more likely to be inspired to go hide in a log cabin somewhere in the mountains.

America's antagonists become more exuberantly confident with each day, like newcomer Julian Ninio, who credits Noam Chomksy as the inspiration behind his book The Empire of Ignorance, Hypocrisy and Obedience. Chomsky is Old Testament prophet to Ninio's brash young messiah. Ninio wants to save America's soul. But Ninio isn't so much a thinker as he is a summariser of the central issues that pre-occupy Chomsky and the other critics. There's nothing new here. Ninio, a Harvard MBA (what else?), describes America as a country in desperate need of a cure. Life is getting harder everywhere (terrorism, environmental destruction, economic woe) and, "because today America has such economic, military and cultural influence, no one can seriously contemplate changing the world without changing America".

A daunting 13-page list of "America's ills all in one place" floats like a pool of black in the middle of the book. The reader is invited to plunge into a series of lugubrious statements such as: "When 500,000 deaths reinforce our power, politicians say `the price was worth it'." "Government agencies silence critics thanks to rights that interfere with our right of free speech." "Our corporations pressure foreign countries to let our corporations kill their citizens and destroy their nature." "We use terrorism, we attack countries, we carry out war crimes." And so on.

There's scant evidence presented to substantiate these putative crimes, but Ninio knows his market. You'll probably buy this book if you have already decided that America is a brute. Ninio recommends the writing of polite letters to Americans you've never met (you get their addresses from the internet white pages) to beseech them with sentences like, "I have nothing against American people like you. But I disapprove of what your government does outside America." A letter which would end up in the trash faster than a department-store catalogue.

Michael Moore rivals Chomsky in prominence, but unlike the good professor, Moore's books are readably accessible. Moore is vicious, he's funny, his timing is impeccable. He's also self-important and shrill. And while he likes to play "ordinary Joe", his discontent earns him a fortune. He reaches millions in every possible medium - books, films, TV, his own website, www.michaelmoore.com. 

He's in danger of becoming a demagogue.

Moore's latest volume Dude, Where's My Country? is a typical example of his art. Osama bin Laden is "a rich ---- who kills people". Americans are "all hepped up on Prozac and cable television so that we always believe what our leaders tell us". On America's support of suspect regimes like the Saudis: "We've picked more losers than a television executive."

Just how did Australia become part of the coalition of the willing? Because "Bush dangled the prospect of a free-trade agreement in front of Australian Prime Minister John Howard". We were bribed. So where's the proof, Mike? Is it not possible that Howard believes in what he is doing - even if he's wrong? There's no room for true believers in Mike's cosmos: everyone lies.

Moore's new documentary, Fahrenheit 9/11, is the cinematic companion to Dude and re-works its themes. His stated aim is to make Bush so unpopular he'll be voted out at the next election. But in Moore's corrupt America, the evil capitalists are so entrenched that removing an "ignorant" puppet like Bush would make bugger-all difference.

Moore's criticisms are hardly original; they're an expanded version of novelist and essayist Gore Vidal's. In Dreaming War , a compilation of vitriolic essays, Vidal expounds identical material. Bush was "not legally elected" but put in charge by the Supreme Court "in the interests of the oil and gas and defence industries". Vidal also points to Bush's business dealings with the bin Ladens. The conquest of Afghanistan has "nothing to do with Osama". He was a "pretext" to replace the Taliban with a friendly government that would allow an oil pipeline to access the rich Caspian Sea reserves.

Fund healthcare. Improve education. Cut military funding. Abolish the war on drugs. Vidal has been clamouring about these issues since Moore was in nappies. Incidentally, Vidal should thank George W. Bush - the president's controversial adventures have given him new relevance and a fresh audience. 

Vidal has been a trenchant critic of every presidential administration since Franklin Roosevelt. His America is a "permanent war machine" incapable of good, a rapacious empire since World War II. If Vidal's vitriol is more enjoyable than Moore's it's because his prose style is so polished, urbane and witty. You're so intoxicated by the words, you forget he's a polemicist.

Where are America's defenders in all this? It's ironic that a British journalist, William Shawcross, seems to have produced the most well-argued work of pro-Americana. In Allies , Shawcross produces an elegant defence of regime change in Iraq and of America's superpower status. He describes anti-Americanism as the new rock'n'roll.

Reviewing history, Shawcross seeks to remind us that "Europe depended on the US for its security for 60 years". Twice during the last century Europe may not have survived totalitarianism. Without the US, it "might either still be collaborating with Nazism or be under control of the Soviet Union".

After World War II, America sponsored and led the world's reconstruction. "All Europeans have America to thank for the success of the Marshall Plan and all subsequent US assistance." Superpowers have their uses.

For Shawcross, removing Saddam was morally correct and should have been done years ago. 

And if mistakes were made in exaggerating the possibility of Saddam having weapons of mass destruction, this was only because the hideous knowledge of Saddam's atrocities were sadly not enough to provoke the world into removing him.

The so-called Coalition of the Willing, Shawcross reminds us, includes 30 countries, not just the US and Britain. Removing Saddam had its fans. He quotes East Timor's Nobel prize-winning activist Jose Ramos-Horta as being appalled by the peace marchers. "If the anti-war movement dissuades the US and its allies from going to war with Iraq, it will have contributed to the peace of the dead."

Although regime change was righteous, we're now in a critical period, Shawcross explains. The rebuilding and healing of Iraq will take years. The US must stay on. And, yes, mistakes were made. America underestimated the difficulty of the task. It should have better informed the Iraqi people of its intentions. It should have closed Iraqi borders to stop the flood of Islamic terrorists. "But for all its faults, American commitment and American sacrifice are essential to the world."

Here's the problem. Commentators seek to give us the facts, but facts can be manipulated. Mustering data to substantiate your argument isn't the same thing as offering proof.

Take the American intervention in Kosovo in 1999 as an example. 

You'll recall that this was ostensibly to prevent Milosovic's Serbian goons from killing and torturing Albanian Muslims. William Shawcross writes that "200,000 people died in the Balkans on Europe's watch. It was America that put a stop to it". Chomsky describes the same intervention as being neither humanitarian nor justified. After the American bombing of Kosovo, "the atrocities picked up enormously". The Balkan bloodshed and the refugee tragedy was brought about by US intervention, Chomsky alleges. Does the general reader have the resources to interview witnesses or plough through the State Department documentation?

Avoiding polemical style and offering an entirely different angle on empire is Bob Woodward's new book, Plan of Attack. Washington Post journalist Woodward seeks here to tell the inside story behind the American invasion of Iraq. Woodward's best sources are his interviews with key Bush administration heavies, including Donald Rumsfeld and the President himself.

We learn that Bush studies "body language, the eyes, the demeanour" to gauge the truth when listening to an adviser. He's more canny than we suspected. George Tenent (the former CIA director) is "high strung, an extremely talented briefer, the son of Greek immigrants". Donald Rumsfeld (Secretary of Defence) remains an enigma to the people because he is so silent. Says Bush: "He should go out and do more interviews."

Plan of Attack is interesting in what it doesn't reveal. There is no conspiracy to grab oil. No sinister cabal. Instead, we find an administration grappling with world events and aware of its enormous responsibility. Bush is strong-minded: Saddam Hussein should be removed in the name of decency. He even thinks regime change may facilitate peace between Israel and the Palestinians. Bush has opinions of his own? 

That would be news to Mike Moore, who would probably call Woodward's book a crock. We're so used to Bush being described as puppet ignoramus, it comes as a shock to have him depicted so fully in control.

A simple-minded anti-Americanism is growing steadily within the republic, threatening to cripple it with self-hatred. Equally crippling, however, is the obvious spinning of facts and factoids by the American Government and its supporters. We are bombarded from both sides not with information, but with rhetoric. We have no real choice but to pick from the side that fuels our own preconceived bias.