Canada's tar sands, which have become a major and secure supplier of oil to the United States, have also been singled out as a major target for American and Canadian environmentalists. Issuing press releases against them, however, is one thing. Going without the increasing flood of oil they are pouring into the American market would be quite another. Two American environmental groups have declared war on the tar sands. One is the Freedom from Oil Coalition whose San Francisco-based director is formerly of Alberta, the province where almost all the tar sands are located. He was in Alberta last week...