In 1988, Stephen Harper wrote a sentence that haunted him and the new Reform Party he had helped create. Conservative leadership candidate Maxime Bernier is now saying something that echoes it.

Reform Leader Preston Manning had appointed Mr. Harper, not yet 30 and still finishing his master's degree, head of policy for the months-old party, which was frantically preparing for the upcoming federal election. Mr. Manning and Mr. Harper co-wrote the Blue Book, a set of policies based on the resolutions of the party's founding convention.

Most of the resolutions were consistent with a party of conservative protest. But one sentence stood out. "While immigration should not be based on race or creed," the Blue Book declared, neither "should it be explicitly designed to radically or suddenly alter the ethnic makeup of Canada, as it increasingly seems to be."

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Mr. Harper loathed that sentence. He rightly feared it would brand Reform as racist and anti-immigrant. He convinced the party to drop the policy in time for the 1993 election. Nonetheless, critics of Reform and of the Conservative Party that Mr. Harper ended up leading would dredge it up from time to time in an effort to brand the party and its leader as racist.

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On Sunday, Mr. Bernier tweeted this sentence from the immigration plank of his platform (you can find it on his website): "Our immigration policy should not aim to change the cultural character and social fabric of Canada, as radical proponents of multiculturalism want." For this writer, that sentence sounds disturbingly similar to the sentence that branded Reform as intolerant and anti-immigrant.

Like it or not, immigration is a key issue in the Conservative Party leadership race. Ontario MP Kellie Leitch appears to be staking her entire campaign on a proposal to require all arriving immigrants, refugees and visitors to be grilled to ensure they embrace "Canadian values."

On the other hand, entrepreneur Kevin O'Leary appears to favour Canada's existing open-door policy — though Monday afternoon he protested refugee claimants who were crossing the border illegally, saying it was "unfair to the thousands in refugee camps legally trying to escape persecution" — while former immigration minister Chris Alexander would actually increase immigration levels once certain economic conditions are met. Other candidates are somewhere in the middle.

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Canada's cultural character and social fabric, whatever that means, are under no threat. There is no substantial evidence that this country is becoming less tolerant, less committed to equality and diversity, less dedicated to preserving human rights and religious freedoms.

And who are these "radical proponents of multiculturalism?" What are they proposing?

With one Canadian in five an immigrant, mostly from Asian or Pacific countries, and with immigrants and the children of immigrants dominating the suburban ridings that determine the outcome of federal elections, any perception of being anti-immigrant is an act of political self-immolation. If Mr. Bernier wins the leadership, be assured the Liberals will use that sentence against him.

To be fair, the candidate's overall immigration policy is reasonably moderate: He would reduce intake from the 300,000 target set by the Liberal government to the 250,000 level set by Brian Mulroney and retained by both Liberal and Conservative successors.

He would increase resources for screening immigrants (a nod to Leitch supporters, no doubt) and favour economic-class over family-class immigrants.

The Hill Times reports that many of the same Tamil and Sikh Conservatives who supported Patrick Brown in his successful bid to lead the Ontario Conservatives are behind Mr. Bernier.

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Mr. Bernier's campaign declined a request for an interview, but pointed to this statement from the candidate:

"The overarching objective of Canada's immigration policy should be to fulfill the economic needs of our country. Of course, Canadian society is also transformed by immigration, as it has for centuries. But this has to be done organically and gradually. When it happens too fast, it creates social tensions and conflicts, and provokes a political backlash, as we can see today in several countries."

Mr. Bernier is a brave Conservative, who favours eliminating subsidies to the dairy industry and to corporations such as Bombardier, even though both policies are popular in his native Quebec.

But the fact remains that if the Conservative Party is to return to being a governing party, it must have the support of immigrant voters. If it goes down the path of opposing "radical multiculturalism," the party will languish in opposition for a generation.