Canada's nationalized health-care system, admired by the left all over the world and deplored by the right all over Canada, took another hit last week. The Canadian Medical Association, long its unfailing supporter, suddenly turned against it. The CMA elected as president Dr. Brian Day, a Vancouver surgeon and one-time supporter of state medicine, who is now an outspoken critic of Canada's "Medicare" system. In fact, he runs the largest private clinic in the country, offering an array of surgical procedures to people prepared to pay for them. In doing so, he challenges the Canada Health Act, which prohibits for-profit...