Politics abhors a vacuum, so it is not hard to understand why Al Gore and George W Bush aren't the only candidates in this year's presidential race. Gore, after all, is a Democrat who supports free trade, missile defence and paying off the national debt. Bush is a Republican who can't get enough photo opportunities with minorities, and whose governing philosophy, "compassionate conservatism", is almost identical to new
Both are riding the economic boom, careful to give no hint of radical change. To the many liberals disconcerted by global capitalism and the many conservatives unnerved by the value-free culture of the mass market, they have nothing to offer but
On the outside looking up: Ralph Nader is one of two men the front-runners now have to watch. Photograph: Scott Applewhite
Which is where the newest, two-headed beast in American politics comes in. Ralph Nader of the Green party and Patrick Buchanan of the Reform party are unlikely allies, and for most of the past 30 years they've been diametrically opposed. But they share a new crusade this year - the bludgeoning of the two-party machine - and a new nemesis: corporate capitalism.
The two evils of bipartisanship and corporate capitalism are combined, of course, in their populist imaginations: the capitalists have bought up the two major parties, sold out ordinary Americans, and are fast eroding what's left of traditional virtues in America and around the world.
Fringe freaks? Not exactly. In the polls right now, their combined tally is comfortably over 10%, easily larger than most recent margins of victory in presidential elections. In an election as close as this one is expected to be, their slivers of enthusiasm could matter.
As Bush tacks to the centre, Buchanan is quietly picking up the dregs of social conservatism in the southern Midwest. More dramatically, Nader is running at close to 10% in some western states, scoring particularly well in the pot-smoking, restless enclaves of northern California and the Pacific northwest.
They are odd fellows, each of them. Buchanan is the best known. A former speechwriter for Nixon, television attack-dog of the right, and runner-up in the last two Republican nomination battles, Buchanan in person is shy and mild-mannered, terrified of personal conflict, married with no children, and the kind of man likely to lock himself away for months to read books on American history.
Nader is similarly quirky. Famously ascetic, he first earned national fame in 1965 with his book, Unsafe at Any Speed, a screed against General Motors' Corvair car. When GM fought back with a personal campaign against him, Nader sued for invasion of privacy and won.
For the next couple of decades, he made a reputation taking on big corporations in the name of consumer safety, setting up a formidable array of public interest groups across the country, and pioneering a lonely politics of liberal zeal. These days, he seems like a cross between Esther Rantzen and Enoch Powell, striding the political landscape like some petty anachronism who won't quit.
But the energy he has tapped into is real. Take this passage from his acceptance speech to the Green party convention: "Through television, the internet stores, samples and mailings . . . companies convey their message to the little ones. They teach them how to crave junk food, thrill to violent and pornographic programming, interact with the virtual reality mayhem.
"The marketeers are keenly aware of the stages of child psychologies, age by age, and know how to turn many into Pavlovian specimens powered by spasmodically shortened attention spans as they become ever more remote from their own family."
It's a wonderful melding of conservative and liberal paranoia. Buchanan has finessed the same formula. At once suspicious of corporate America, opposed to the World Trade Organisation and the North American Free Trade Association, Buchanan is also passionately opposed to abortion, to equality for homosexuals, and to much of Hollywood.
He and Nader represent that oddly evanescent mixture in American politics - a liberal economics and a social conservatism. Nader shares Buchanan's hostility to free trade and big business, although he's far more liberal on issues such as abortion and gay rights.
But his concern for the anonymity and rootlessness of online America is oddly complementary to Buchanan's more familiar reactionism. In one of Nader's more striking campaign riffs, he even voices this explicitly: "[My] goals are also conservative goals," he argues.
"Don't conservatives, in contrast to corporatists, want movement toward a safe environment, toward ending corporate welfare and the commercialisation of childhood? Don't they, too, want a voice in shaping a clean environment rooted in the interests of the people? Don't they, too, want a fair and responsive marketplace, for their health needs and savings?" Sure they do, is Buchanan's reply.
Nader and Buchanan are men who came from nowhere to challenge for the highest office. They are not sons of former presidents or senators; and where the two main parties seem increasingly fake, the sincerity of both Buchanan and Nader is not in much doubt.
In my view, they should be allowed into the presidential debates, if only to make them half-way interesting. They won't be, because the debate commission is a stitch-up between the two big parties, and because American elections are almost always fought over half an inch in the centre rather than half a mile at the fringe.
But, for all their eccentricity, Buchanan and Nader at least represent something real, and something any political system should be able to absorb. It's a sign of America's political health that they are threatening to make Gore and Bush watch their backs. And a sign of Bush's and Gore's weakness that what's behind their backs is so much more interesting than what's in front.
Copyright 2000 Times Newspapers Ltd.