It is often hard to explain to foreigners what an American presidential election is actually about. We cling to a two-party system in the same way that imperial Rome clung to the republican notion of two consuls as figurehead - to mark off, if nothing else, the years that they held office conjointly. They reigned ceremonially but were not makers of the political weather. Our two official parties have, at times, dedicated themselves to various issues, usually brought to their attention by a new president with a powerful popular mandate - hence the New Deal of Franklin Roosevelt, which gave, if nothing else, hope to a nation sunk in economic depression.

Later, as he himself folksily put it,"Dr New Deal has been replaced by Dr Win the War". Dr Win the War, whether he calls himself Republican or Democrat, is still providing - in theory - employment and all sorts of other good things for a people who did not emerge from the Depression until 1940, when Roosevelt began a military build-up. Sixty-four years later, like a maddened sorcerer's apprentice, he continues to churn out ever more expensive weapons built by an ever-shrinking workforce.

Since the US media are controlled by that corporate America which provides us with political candidates, an informed electorate is not possible. What the media do well is not analyse, or even inform, but personalise a series of evil enemies, who accumulate weapons of mass destruction (as we constantly do) to annihilate us in the night out of sheer meanness.

How, then, will a people grown accustomed to being lied to about serious matters behave during an actual presidential election, in which billions of dollars have been raised to give us a generally false view of the state of our - their? - union. Right off, half the electorate will not vote for president. Those who do vote sometimes exhibit unanticipated trends. In all the recent polls (easily, alas, rigged by the way the questions are posed) the conquest of Iraq is more and more regarded as an expensive mistake: the $ 87bn (pounds 48bn) that the President has now asked for to repair that country and which Defence Secretary Donald Rumsfeld joyously knocked down in order - it now appears - for his colleague, vice-president Dick Cheney's company Halliburton to rebuild. Americans in general seem to have got the point of the exercise. So during this primary season - a rehearsal for the November election - is anything happening politically? Quite a lot for those who know how to read the Pravda-like Murdochian media.

First, a vast, spontaneous anti-war movement has been holding huge rallies (mostly unreported by the media). I addressed 100,000 people on Hollywood Boulevard. The press pretended no one much was there that day, but a subversive picture editor ran a photo of the missing (in print) 100,000 anti-war protesters, stretching from La Brea to Vine Street and filling up the boulevard. In the Democratic primaries, an obscure governor from Vermont tapped into the anti-war fervour that was building across the country.

I am writing a few days before the first Democratic primary. Although Governor Howard Dean had a strong lead for many weeks (if Murdoch TV is to be trusted), he is currently tied with the Massachusetts Senator John Kerry and Representative Dick Gephardt, each running as anti-war candidates (despite the fact that they both voted to give Bush wartime powers, leaving Dean the most immaculate of the anti-imperial candidates). Should Bush lose (a possibility not even whispered in TV land) it will be entirely due to one of the most ancient reflexes of the American electorate: a dislike of foreign wars in general and imperial wars in particular.

Recall Ulysses S Grant, a great man and a great general but a failed president, reflecting upon our war of aggression against Mexico. As a young lieutenant, recently graduated from West Point, Virginia, he fought dutifully against Mexico in 1846. Later he registered his hatred of that war. To us it was an empire, and one of incalculable value, but it might have been obtained by other means. The Southern rebellion was largely the outgrowth of the Mexican war. Nations, like individuals, are punished for their transgressions. We got our punishment in the most sanguinary and expensive war in modern times.

The true American imperialist would find our greatest general and winner of the civil war sentimental! After all, the war that we fought against Mexico gave us California and half a dozen other states. And wasn't the 1860 civil war about the abolition of slavery? No, it was not, but our historians tend to be cut from the same material as the media. A lie repeated often enough is, plainly, the truth. Bush told us so often that Saddam Hussein was in league with al-Qa'ida and the 9/11 attack on the US, that 60 per cent of Americans still believe this to be true. Even so, the anti-imperial movement is growing throughout the land; and it now gives unusual substance to the present election.

General Wesley Clark is viewed by some as a potential General Boulanger. But whatever he is or will be, he too is on record as saying that the war in Iraq was the wrong war at the wrong time in the wrong place. He is rising in the polls, despite having no discernible gift for American- style politics, as well as attracting numerous hate pieces about him in the press - the work often of jealous, lazy generals.

So the feckless Bush has not only given new meaning to the equally feckless Democratic party but he has, despite the best - that is to say, the worst - efforts of the media, given new meaning to our corrupt political system. The United States, on top of the world - or so it appears to think - is dividing consciously between imperialists eager for us to seize all of the world's oil resources, and the anti-imperialists who favour peace and renewable sources of energy. The media are furious at this departure from the norm, which is lies and insults about the personalities of the contenders. There is also a certain unease about the essential crookedness of the political system, which is now apparent to nearly everyone.

Perhaps the election after next - should we survive this one - will have as its subject the necessity of a new constitution, obviously a dangerous but inevitable notion. That is when the most eloquent of the presidential candidates this year, Dennis Kucinich, will come into his own. He is already shaping up as a leader of an as-yet-unborn progressive alliance. Naturally, he is branded a leftist, the word used for any thoughtful conservative. Actually, we have never had a left or even a conscious right. We divide between up and down. The downs may now be on the rise.