Since Alexa McDonough started talking of remaking the NDP in the image of a modern social democratic party, such as Tony Blair's "New" Labour party in Britain, some of her friends on the left, among them the leaders of the country's biggest unions, have been heard making choking sounds. Their ideological indigestion is such that some, such as Buzz Hargrove, head of the Canadian Auto Workers, are even talking of starting a new party.

"I think this will cause a lot of people to re-evaluate their commitment to [the NDP]," Mr.

Hargrove spluttered to a National Post reporter last week. "What we need is a party that clearly defines policies that will rebuild people's confidence in the left." His colleague Bob White, the chairman of the Canadian Labour Congress, agrees. "I don't think there's much space where Alexa is trying to take us." Some New Democrats may be inclined to challenge Mr. Hargrove's own commitment to the party, given his recent suggestions that his union might lend its support to the Liberals in some ridings in the forthcoming Ontario election, if this would make the defeat of the Tories more likely. Nevertheless, he and Mr. White have a point.

It's all very well for Ms. McDonough to talk of "repositioning" the party, as if it were a brand name that had gone stale. But what does it mean to be a New Democrat, in that case? If a party seeks principles in order to win power, rather than seeking power to put its principles into effect, what remains of that party's identity? What has it achieved, but to reflect back to the voters ideas they already hold?

If, on the other hand, Ms. McDonough truly believes the NDP's traditional policies to have been, not just unpopular, but mistaken, then an even more serious existential crisis is upon the party. There is certainly room on the political spectrum for a party that, while a staunch advocate for social equality and the caring state, also stands for the market economy, balanced budgets, cutting taxes, and free trade. Unfortunately, Canada already has such a party: the Liberals.

In fact, we have three such parties, since the same description could as well apply, with only minor adjustments, to the Reform and Conservative parties. This is the dilemma that today faces all political parties. The politics of contrast with which we have been familiar for most of this century, in which fundamentally opposing visions of society clashed head-on, have been replaced by the politics of convergence.

For many supporters of the left, this is a betrayal not only of socialism, but of democracy.

Tony Benn, the hard-left British MP who represents the Old Labour wing of the party, grouses that Mr. Blair and others like him "want to offer us a choice of management styles, not a choice of systems." By comparison to the vast panorama of conflict presented by the old politics, the new politics seems to promise little more than a series of unexciting skirmishes.

But who says that politics has to be about a choice of systems? For that matter, who says politics has to be exciting? The idea, so natural to us, that political debate must inevitably be a battle between different economic philosophies is of comparatively recent vintage.

Which isn't to say that politics before then was trivial or dull. It was just about other things.

In fact, many of the fiercest debates of previous centuries turned on matters on which there is now a high degree of consensus: whether other faiths should be tolerated besides that of the established church, for example, or whether democracy should be preferred to more autocratic systems of government.

Is it not possible that, just as we have reached consensus on the appropriate political system, we might also have reached the same broad consensus on a social and economic system? No one complains that every political party believes in democracy. Is it any more unnatural that every party -- including, it seems, the NDP -- should come to share the same basic economic philosophy?