According to Daimnation it is that they are among the few who will not allow a mix of private and public health care.
...Klein specifically rejects the costly American model, but you know that isn't going to stop Shirley Douglas from squawking about the "Americanization" of Canadian health care. As with many issues in Canada, that may be enough to shut down debate altogether.
What would the Liberals do without the American boogey-man?
