The Coastal Voices blog at Living Oceans had an intersting post up remarking on the disparity between Canadian's self-image as environmental progressives and reality---that they appeaer to lag the U.S. in marine protection and other conservation issues. The author wondered why this might be. I left a comment, which I'll expand on here.
I've had similar thoughts and my guess is this blind spot for domestic environmental issues owes to Canada's: (i) vast wild-lands (natural resources), (ii) very low population and (iii) long-standing economic dependence on extraction of those resources. Canada is simply less far along in 'using up' its domestic natural resources, and thus less steeped in the urgency of purpose that comes with realizing human uses can exhuast nature's bounty.
From my vague understanding of history, nature's inexhaustability was unquestioned during early European settlement and the bounty of the Territories consistently awed settlers during westward expansion. The gradual 'filling up' of the U.S. and concomitant loss of wilderness and formerly abundant species eventually fostered a movement to conserve wild lands for their own sake (or at least for the sake of hunting).
I don't think the U.S. 'lead' on these issues owes to anything other than our other lead---on using up our finite resources. Of course, despite that other lead, U.S. laws aren't as strong as they might be---in particular environmental-protection measures typically defer to entrenched local users---so I guess both U.S. and Canadian attitudes about conservation could use a bost.