“The only job she cares about is her own,” he said at a campaign stop in Kamloops - NDP Leader John Horgan 

I imagine that is an overstatement but that there is more than a foundation of truth in the statement. However, if Horgan really cares about the environment, he would support such a plan regardless if it was his party or Clarke's implementing it and he would back the plan rather than attacking it (nothing to prevent him from also adopting it as his own position). 

Electricity runs North-South in North America, not East-West.  Turn off the lights, the flow of fresh water and of Canadian oil to the Yankees and they will quickly learn about the importance of NAFTA (while the US is now a net-exporter of Oil again, many refineries have been overhauled to process Canadian heavy crude and converting to other sources is a lengthy and costly endevaour).  

That said, hopefully the NAFTA assault brings an end to Dairy Supply Management. A scourge if there ever was one.