"I think one of the things that we have to know is that this can cause huge upheaval in the province's ability to control their natural resources and real problems for Canada's sovereignty long-term," Tom Mulcair said in an interview with The Canadian Press.
Control over resources is a particularly prickly topic in Alberta, where Mulcair was making a stop to support anti-poverty advocate Dan Meades, the party's candidate for Calgary-Centre in a Nov. 26 byelection.
Mulcair has said previously that a New Democrat government would do anything in its power to extricate Canada from the Foreign Investment Promotion and Protection Agreement if it's found to not be in the country's best interest.
"I think the average Calgarian and the average Albertan understands very well that the battles that were fought 30 some-odd years ago to get control of natural resources put in the constitution shouldn't be thrown aside easily," Mulcair said at Meades' campaign headquarters, where volunteers were busily working the phones in the next room.
"People are starting to realize that this could play havoc with the province's ability to control their resources going forward."
The separate, but related, issue of a state-owned Chinese company's $15.1-billion takeover of Nexen Inc. (TSX:NXY) has been top of mind for voters in the downtown Calgary riding.
Calgary-Centre is where Nexen's headquarters are located and it's where China National Offshore Oil Co. has promised to base its North and Central American operations.
After two extensions, a federal decision on whether the Nexen deal is of net benefit to Canada is expected on Dec. 10. The NDP and other critics have derided the review process as being too vague and secretive, though the Conservative government has said it would clarify its guidelines soon.
"The big question that people seem to be asking is what are the Conservatives hiding?" asked Meades. "Why is it they won't tell us how this decision is going to be made? Why is it they push it off again until after the byelection?"
Meades said he believes the NDP has a "great shot" at winning the riding in the heart of Tory country.
"The people of Calgary have a real penchant and kind of history of thinking for themselves and voting on the best ideas and the values that represent them," he said.
However, Mulcair reiterated some points that have in the past rubbed many Albertans the wrong way.
He stood by his assertion the Canadian dollar is being driven artificially higher because the resource industry is getting a "free ride" when it comes to paying the environmental costs of extraction.
He said that, in turn, is hurting the manufacturers in Central Canada that are having a tougher time exporting their goods — a phenomenon known as Dutch disease.
He called the proposed $6-billion Northern Gateway pipeline connecting oilsands crude to the West Coast port of Kitimat, B.C., a "non-starter" on environmental grounds, adding that approving it would be a "historical mistake."
And Mulcair again took aim at the Keystone XL project, which if approved would significantly increase the amount of raw oilsands bitumen Canada ships south of the border.
Doing that will sacrifice upgrading and manufacturing jobs, he said, suggesting Canada should instead look to process the crude at home.
The NDP is, however, on record as supporting proposals to ship crude from western Canada to refineries in Ontario and Quebec, since it would allow those facilities to buy cheap Canadian crude rather than pricey international varieties.
"We think rather than going that way, more to the States, we should take care of our own energy security first," said Mulcair.
"That would be a win-win-win situation. A win for the producing provinces, a win for the companies that have their own ownership of what they've bought or leased and a win for the country because we'd be providing greater energy security for the future."
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