After a long-standing silence on Keystone XL, Hillary Clinton, the U.S. presidential front runner, has come out opposing the pipeline proposal to carry tar sands oil from Canada to the U.S. Gulf Coast.

The news, which broke earlier this week, is a huge win for the climate movement.

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Yes, the ultimate decision on Keystone XL rests with U.S. President Obama, who has balked at the jobs numbers and signalled multiple times that he will likely reject the proposal,  which is still awaiting a presidential permit to cross the border six years after originally being proposed. Obama has said he can’t approve the pipeline if it will increase carbon pollution, and since it clearly will, it’s hard to imagine he’ll do anything but reject it.

But Clinton’s opposition to Keystone XL should be considered a win because her stance shifted significantly as a result of the growing climate movement in the U.S., which is part of a growing global movement calling for meaningful climate action.

Clinton previously said she wouldn’t take a position on the pipeline because she didn’t want to interfere with Obama’s deliberations on the project. Prior to that, as Secretary of State, she seemed to express support for the project. That she has moved from an appearance of support, to silence, to vocal opposition is huge.

Climate change has become a major issue in the lead up to the U.S. presidential primaries, and Keystone XL is the flash point for that debate, so much so that Clinton could no longer duck on the pipeline.

In the words of VOX columnist, David Roberts, “Clinton’s shift is a testimony to the extraordinary work done by the climate movement…” The growing climate movement has created a “political landscape in which a national Democratic candidate simply can’t afford to be on the wrong side of the issue.”

The latest blow to Keystone XL may cause TransCanada to double its efforts on Energy East, the company’s other mega-pipeline proposal, but this one intended to carry tar-sands oil from Alberta to Canada’s East Coast. However, the move by Clinton makes this proposal less, not more, likely.

Like our southern neighbours, the climate movement is growing stronger here in Canada. Some 25,000 people gathered in Quebec in April to demand climate action. Then in July, 10,000 took to the streets of Toronto calling for a just transition to a low-carbon economy. The movement, which includes organized labour, aboriginals, students and many others, is incredibly diverse and growing. In addition to showing up in record numbers, the Canadian climate movement also has some concrete wins under our belt.

The Northern Gateway pipeline is effectively dead. Hearings on the Trans Mountain proposal through B.C. have been put on hold. The Line 9 reversal, though approved, still hasn’t begun to flow. And Energy East has been delayed by at least two years because TransCanada had to abandon its plans to put a port in an endangered Beluga Whale habitat on the St. Lawrence.

All of these wins are slowing the growth of the tar sands, and thereby slowing the growth in carbon pollution. And they’re forcing a serious conversation about climate change in this country.

That conversation here in Canada and the U.S. is ongoing. There’s still work to be done before Canada can restore its reputation on climate and put in place a real plan to cut our emissions. But Clinton’s shift on Keystone XL is a sign that politicians recognize that the public demands action on climate and that progressive leaders cannot afford to be on the wrong side of this issue.

And so the U.S. climate movement celebrated a win this week. And we celebrated with them. The momentum is building. We’re winning.

Now, channel the momentum from south of the border and tell our elected leaders to be climate leaders. Like Clinton, they need to recognize that they cannot afford to be on the wrong side of this issue either.