Stéphane Dion, who came from fourth-place standing to win the leadership of Canada's Liberal Party early this month, declared immediate war on the minority Conservative government last week, and made it clear he is determined to force a late-winter election. Implicitly, he made something else clear. He will attack the government on two principal issues, both of them integral to Canadian-American relations. One is the Kyoto Treaty, the other the Canadian role in Afghanistan. If he wins the election, therefore, America's northern neighbor will once again become vaguely hostile territory, as it was under the last Liberal government. On Kyoto,...