Fellow columnist William Watson (June 1) accuses me of complacency over the threat of separatism if Meech Lake fails. I accuse him of complacency over the threat of separatism if Meech Lake passes - separatism in fact, if not in name. So at least we're agreed on one thing.

My original point, to which Watson took exception, was that whether we stitch together something we can prop up with ''Canada'' around its neck in the end is unimportant. What matters is whether we will function as a nation, with a national consciousness. In the likely event that Meech Lake passes with its essentials intact, I do not think we will.

Yes, Bill, it is worth worrying over the possibility of a surge in separatist sentiment should the accord collapse. The situation is plainly volatile in Quebec. But we cannot become so paralyzed by fear that we simply shut down the circuits. That, you'll remember, was John Turner's tactic in the last election. It is Brian Mulroney's now. If it were just a matter of competing national visions, your draft of the constitutional speech vs mine, then fine - hold your nose and pass it. But this rests on two false, or at least questionable, assumptions. First, that Quebec would necessarily and inevitably demand independence (or sovereignty-association, or some kind of ''superstructure,'' or something else) if Meech failed. Second, that Meech would prevent this.

Of the first, I have already expressed skepticism in previous columns. But of the second, you don't have to take my word for it. Listen to Robert Bourassa, or Gil Remillard, or Lucien Bouchard - or, for that matter, Meech supporter Stephen Lewis, if you can bear it. Meech Lake is not the end. It does not ''solve the Quebec problem.'' It is merely the beginning.

It is designed to ''establish on a solid basis the foundations of a comprehensive constitutional reform to come,'' as Remillard put it recently. The ''peace'' it buys will last until the next charter judgment, or the next first ministers' conference, whichever comes first.

But you have clearly misunderstood my argument. It is not the prospect of the federal government losing powers that concerns me. It is that the provinces will gain them. The ''fulcrum of Canadian nationhood'' is certainly not a national day- care plan. That was the error of Canadian nationalism: to think that national identity could, or should be, designed and delivered from Ottawa.

But I didn't say that nations are not defined by ''a set of ideas or policies.'' For New World countries like Canada, lacking the traditional sources of nationhood, they most emphatically are. Only: (a) they need not be different from those of other countries, nor (b) be predetermined by some imagined national attributes. It doesn't matter what ideas are chosen. What matters only is that they are ours.

Nationhood is indeed ''a process.'' It is the act of choosing the ideas that guide our lives. It is a collective process, composed of individual acts of choice, through which the individual discovers his community. The nation is not defined by the state, except indirectly: it is that which defines the state. Hence the urgent need for a more participatory politics in Canada. It is not just a point of democratic principle. It's the only chance we've got.

How then does Meech Lake destroy our nationhood? Because it amounts to governments turning their backs on the people, excluding them from the process. Because it is designed for provincial governments, through the powers they have won, to repeat the Canadian nationalist mistake at their own level. Because it encourages us to retreat into ever-narrower group allegiances - the Acadians are already talking about autonomy from New Brunswick - rather than to discover, through the nation, the wider allegiances we owe humanity. We all love our families. But the nation is the first experience most of us have of loving someone we have never met.

We may still inhabit the same northern shelf as Quebecers under Bourassa's beloved ''superstructure.'' But we would no longer participate together in the same collective process of discovery. We would be spared the discomfort of having to know the Other, those so seemingly different from ourselves, instead of huddling contentedly with our own kind. Scoff if you like, but comfort and contentment have nothing to do with my - and Rilke's - definition of love: the intimate awareness of another solitude.

That is a good part of Canada's moral claim to being. And if there is not to be a purpose to Canada, if it cannot stand for something nobler than a common market, than I wish the name were dead.