The oldest saw in modern politics is that elections are won only on the centre ground. Extremists have to abandon, or at any rate disguise, their passions, and move to positions as close to being all things to all fickle voters as they can invent. That's how Tony Blair made Labour electable. The coalitions of continental Europe are built round the same inescapable proposition. In such politics, nuance replaces conviction, and manoeuvre boldness, as the identifying marks of a winning team. What's going on in America as the 2004 election begins is unnervingly the opposite. It's one of the more extraordinary spectacles a political scientist, or journalist, let alone a professional politician, could encounter. George Bush is running his campaign from the same fringe position as the one he has adopted for his presidency.  This is a hard-right administration offering virtually no concessions to the soothing niceties that might make it more electorally attractive to voters who are not Republicans. Its tax policy is grotesquely loaded against the masses and in favour of the rich. Its bias on the environment unfailingly comes out on the side of the big commercial interests. It is daily tearing up tracts of policy and practice that protected the basic rights of people snared in the justice system. It is the hardest right administration since Herbert Hoover's from a very different era. And, which is the point, delights in being so. There is no apology or cover-up.  But even that isn't the most striking thing about the set-up as it now stands. For this we have to turn to the Democrats. Unlike Bush, many Democrats are sticking to the conventional wisdom. They grope for some kind of centre ground. But so far has the territory shifted, thanks to the Republicans' shameless stakeout on the hard right, that their quest continues to drain their party of most of its meaning and any of its capacity to inspire.  The rules are being observed, but we find that in some circumstances these rules are a fallacy. They draw a party so far into the orbit of its rival as to render itself meaningless as anything except a political machine of variable potency around the country. Yet the dominant mode of most presidential candidates is still to cling to the kind of centrism that defines them at best as Bush-lite, at worst as people who have nothing to say that could send the smallest shiver up the spine of afloating voter.  One should hesitate to second-guess all these massively professional politicians, laden with polls. But their reflex looks to me as unnecessary as it is self-destructive. One way to respond to Bush's rewrite of the rule book - which covers more contentious ground than Ronald Reagan's campaigns ever did, for example - may be to meekly accept the new setting for old maxims. The other is to treat the maxims, in present times, as a snare.   For one thing, many Democrats seem to have forgotten that they did win the election last time. For four years it has been idle to challenge the Florida vote and the bizarre workings of the electoral college, but now is the time to recall that in 2000 half a million more Americans voted for Al Gore's progressive version of the future than Bush's more conservative one. Bush was still posing as a bit centrist then, and Gore was scarcely a raving liberal. Gore mostly stuck to the Clinton third way doctrine that had taken the Democrats away from the narrowest version of their past. But there was a left-right choice, and more Americans voted left than right.  In most systems, that would have been another reason for the technical winners to gravitate towards the centre. Since that did not happen, it is instead an excellent reason for the losers to rediscover their raison d'tre. Yet most of them seem mesmerised with terror at the prospect, and full of guff about Democratic "values" which they take to excuse them from advancing any awkward Democratic policies.  The Iraq war is to blame for this, but only partly. It is Bush's alibi for everything   else. To the extent that voters dislike his right-wingery on domestic matters, Iraq and terrorism give cover to the Great Leader. We may be sure he will exploit this until the day of the election. It puts Democrats in a bind, though something has changed when dreary Joe Lieberman, an early war supporter, now feels it necessary to bleat defensively that his was a "principled" position, and posturing John Kerry - probably the favourite as things stand - calibrates a position edging finely away from believer to mealy-mouthed critic. Another year of Baghdad body bags, with Osama bin Laden still at large, and the politics of the war cannot be so neatly predicted.  For any Democrat to take advantage of Bush's waning popularity and overcome his vast campaign finances, however, he must have something to say. There needs to be some clarity, on all fronts. The other day, the same edition of the New York Times carried stories saying that neither young African-Americans nor the Boston Irish could any longer be counted on as part of the core vote. Is this heresy surprising when nobody knows with any certainty what Democrats stand for? If a party can't fire up its core vote, it will be deader quicker than if it can't draw in people who've never voted for it before. Watching what Bush has done to both the economy and the constitution, it should be easy for a Democrat to come up with soundbites and articles of simple faith to inspire a few more than the millions of Americans who voted for Gore last time.  Wiseacres continue to pretend otherwise. They think Howard Dean, the most lefty of the candidates, and former governor of the state of Vermont, could never get elected. Transfixed by the attractions of triangulated centrism, they're prepared to have its geometry laid out exclusively by their opponents. They come out against a bit of the Bush tax plan but not all of it. They're all but silent, as are much of the media, on what anti-terrorism psychosis is doing to civil liberties.  Yet the Republicans didn't get where they are today by such half-baked timidity. The challenge they make is for the life and death of the soul of the America very many Americans still believe in. What their opponents need is a leader whose voice rings more eloquently than Bush's - surely not the hardest contest to win. That won't happen until they abandon their backing and filling, and their belief that being a Democrat no longer adds up to anything more than a milder version of their enemies.  "Extremism in the defence of liberty is no vice ... Moderation in the pursuit of justice is no virtue." Barry Goldwater said that 40 years ago. It was the start of the recovery of the right. The words now belong rather exactly in the other side's mouth. If they came out of Senator Kerry's this autumn, they'd make him sound less like a calculating wimp.