After Justin Trudeau had vowed his government would act to avoid the "tragic and devastating consequences" and "truly catastrophic effects" of climate change, invoking his three children by name as he spoke of the world we will leave to future generations, the Conservative critic stood and lamented that the prime minister wasn't being very nice about it.

"Why," Ed Fast asked, "is he using a sledgehammer to force the provinces and territories to accept a carbon tax grab and what happened to his promised new era of co-operative federalism?"

Trudeau's move had something in common with that time several years ago when Conservative finance minister Jim Flaherty walked into a meeting of his provincial counterparts and told them how he would be funding health care.

Though in this case the prime minister did at least sit down with the premiers a couple times before he, in Fast's words, "lowered the boom."

But if, 50 years from now, the worst that can be said of Justin Trudeau's implementation of a national plan on climate change is that he wasn't terribly polite about it, he will have presumably done fairly well for himself.

For today, he has at least acted to commit himself to a specific action.

"With two months left before the first ministers' meeting, and no consensus at the table, it was time to act," says a government source.

Shock and awe in Ottawa and Montreal

On his government's most consequential and surprising day to date, Trudeau arrived in the House of Commons a minute before noon, his hair freshly cut. Taking his seat, he was compelled to wait a few moments for debate to conclude on a proposal to establish a National Seal Products Day.

Trudeau outlines his climate change plan 1:34

With that concluded, he stood in his spot, then returned to his seat upon realizing it was not yet his turn, then stood again a half minute later when the Speaker formally called on him to begin debate.

On the table, officially, was a motion to consider the government's decision to ratify the Paris Agreement on climate change. In the short stack of speaking notes on Trudeau's desk was something more specific.

"It is in that very Canadian spirit of solving problems and keeping promises that I address the House today and share the government's plan for pricing carbon pollution," he said, leaving a little pause between each of those last three words.

A bit more buildup, and suddenly, there were numbers, stated en francais and then repeated in English.

"The government proposes that the price on carbon pollution should start at a minimum of $10 per tonne in 2018, rising by $10 each year to $50 per tonne in 2022."

And then the kicker.

"If neither a price nor cap-and-trade system is in place by 2018, the Government of Canada would implement a price in that jurisdiction."

When the prime minister concluded his remarks, Stéphane Dion left his seat and walked over to shake Trudeau's hand.

'It is our view that this has to be concurrent with a pipepline,' Alberta's premier said Monday. 0:41

Two hundred kilometres away in Montreal, the federal and provincial environment ministers were in a conference room at the Marriott Château Champlain. And as Trudeau stood in the House of Commons to declare his government's intentions, Environment Minister Catherine McKenna rose on an intervention to inform her provincial and territorial counterparts of what was happening in Ottawa.

"There was quite literally shock," one source told CBC News.

"The air was sucked out of the room," reported Yukon cabinet minister Currie Dixon.

The government's timing, during a meeting of environment ministers, is certainly interesting, even if an anonymous source had called this carbon-pricing shot as far back as March.

The delegations from Saskatchewan, Newfoundland and Nova Scotia made a show of walking out in protest.

But British Columbia, Alberta, Ontario, Quebec and the rest were not so aggrieved. (And now Manitoba isn't ruling out a carbon tax.)

At question period, Trudeau would have some fun informing the House that Quebec's premier was quite appreciative of the government's plan, although Fast attempted to cite previous comments of the province's environment minister to suggest otherwise.

Trudeau's Goldilocks defence

Much remains to be seen and done.

The price commitment by the prime minister will not be enough to achieve the reductions necessary to meet Canada's target for 2030, so other policies will have to follow, or this will seem much ado about not enough.

Saskatchewan is unimpressed and previously threatened legal action. And Alberta has now made its support contingent upon "serious concurrent progress on energy infrastructure," which presumably means the Trudeau government is going to have to approve at least one of the pipeline projects on offer.

Likely working to the Liberals' advantage is the fact that the federal opposition is neatly divided between those who don't like the sounds of this, but who don't quite have a counter-offer (the Conservatives) and those who don't think this is nearly enough (the New Democrats and Greens).

Noting as much on Monday, Trudeau claimed a Goldilocks-esque balance to the Liberal position, but he now must defend and explain and implement this policy.

The prime minister still cannot bring himself to use the phrase "carbon tax" — "more direct pricing on carbon" is how he phrased the alternatives to cap-and-trade on Monday — but that is the charge that will be hung on his policy by Conservative critics (though Patrick Brown and Michael Chong might at least complicate that complaint).

However defensible, action on climate change raises concerns about cost, economic strife and failed investments.

That debate might be fought for years. For now and for a while yet, there will be a certain question of manners.

Is climate change the new medicare?

In prefacing his announcement this afternoon, the prime minister invoked earlier achievements such as the Canada Pension Plan and medicare (an allusion he has made before in discussing climate policy)

It is Lester B. Pearson's government (with a profound assist from Tommy Douglas) that is credited with the achievement of national medicare. But, with provinces slow to join, it was Pierre Trudeau's government that finished the deal with the imposition of a national tax for health care that would apply to a province's citizens regardless.

John Robarts, Ontario premier at the time, condemned the move as "medicare by coercion" and a "Machiavellian scheme that is in my humble opinion one of the greatest political frauds that has been perpetrated on the people of this country."

And maybe it was. But the country got medicare, a program we have never quite stopped debating, even as it stands as a point of national pride.

If Pierre Trudeau's son ends up with a durable policy on climate change, probably no one will remember that he wasn't perfectly nice about it.