Quebec's leaders spent last week sending ominous signs they don't like how this whole Trans Mountain pipeline thing is shaking out.

Premier Philippe Couillard was standing next to Justin Trudeau in Montreal when the prime minister declared on Tuesday that Ottawa was "determined to see that pipeline built" despite the opposition of the British Columbia government.

Couillard stayed quiet at the time, but grew more garrulous a few days later. "I'd be very careful," he said in comments directed at the feds.

Trudeau's intention to override B.C.'s concerns about the environmental impact of the pipeline was "not a good sign for federalism," the premier added.

Couillard was standing next to Justin Trudeau in Montreal when the prime minister said he was 'determined to see that pipeline built.' (Paul Chiasson/Canadian Press)

On Saturday, Quebec's minister for Canadian relations, Jean-Marc Fournier, circulated an open letter arguing Ottawa was sending the wrong message to the oil industry by backing Trans Mountain so fervently.

The federal government was encouraging "developers to ignore provincial environmental rules which were adopted in the interest of citizens who are concerned or impacted by the implementation of these projects," Fournier wrote.

"Ignoring provincial legislation in no way fosters social acceptability."

Sympathy pains

For the pipeline's backers, Quebec's contribution to the controversy was hardly welcome. It has helped turbo-charge an already sensitive issue. Few can now claim that it's just a local spat between two provinces.

Disgusting and immoral hypocrisy. Quebec takes billions of dollars from Albertans EVERY year, imports their oil from foreign thugs and dictators, but are more worried about attacking Alberta. What is happening to Canada? <a href="https://t.co/r7jzF11G6R">https://t.co/r7jzF11G6R</a> <a href="https://twitter.com/hashtag/ableg?src=hash&ref_src=twsrc%5Etfw">#ableg</a> <a href="https://twitter.com/hashtag/cdnpoli?src=hash&ref_src=twsrc%5Etfw">#cdnpoli</a> —@BrianJeanAB

So why wade uninvited into a debate happening on the other side of the country?

One hypothesis: Couillard is experiencing sympathy pains for his B.C. counterpart, John Horgan.

Couillard could have found himself in a similar position had another oil giant, TransCanada, not dropped its plans to build the Energy East pipeline, which would have carried crude oil from Alberta to New Brunswick.

The pipeline was deeply unpopular in Quebec among federalists and sovereigntists alike. But pipelines crossing provincial boundaries fall under federal jurisdiction. Ottawa would have final say.

To counter its lack of jurisdictional clout, Quebec insisted the pipeline couldn't be built without meeting its own environmental standards.

Trudeau, B.C. Premier John Horgan, left, and Alberta Premier Rachel Notley, sit in Trudeau's office on Parliament Hill for a meeting on the deadlock over Kinder Morgan's Trans Mountain pipeline expansion. (Justin Tang/The Canadian Press)

TransCanada initially balked, but under threat of an injunction, relented and agreed to submit its project to the provincial environmental review board (known in Quebec as the BAPE).

What would Couillard have done had the BAPE recommendations run counter to the federal government's desires?

He was spared that headache when plans for the pipeline collapsed last fall. Unlike with the Trans Mountain project, Ottawa wasn't interested in shepherding Energy East through to conclusion.

Betting on cooperative federalism

But Couillard's reproaches this week are about more than dodging a bullet. His government has invested significant time, and some money, into trying to develop a new dynamic for Quebec within the federation.

Last year, it released an ambitious proposal to revisit elements of the Constitution, hoping to lay the groundwork for someday — maybe, possibly — having Quebec finally sign on.

Trudeau trashed the idea before having read the 200-page document, perhaps envisioning another Meech Lake or Charlottetown.

Both municipalities and Indigenous groups in B.C. have expressed concerns about the environmental impact of the Trans Mountain pipeline. (Darryl Dyck/The Canadian Press)

But it's really just a long argument for cooperative federalism, which boils down to Ottawa seeking provincial input on important issues, even if it doesn't have to, according to the Constitution.

From Couillard's perspective, such a commitment would prevent scenarios such as the one unfolding in B.C., where the feds are pulling rank.

In Quebec, such a move would risk fanning the cooling embers of the sovereigntist movement.

Couillard's wager is that cooperative federalism would prevent such flashpoints of constitutional strife. And in doing so, open the prospect of neutralizing the sovereigntist threat for another generation.

For the moment, though, Ottawa appears intent on heading in a different direction.