Stephen Harper imposed an outer perimeter of control, one suspects, because he worried about his lack of inner control – the fear that he might lose it in public.

Justin Trudeau apparently has no such concerns. He held a town-hall in Nanaimo, B.C., in front of an audience that was vocal and hostile to his government’s decision to back the construction of the $7.4 billion Kinder Morgan pipeline.

As he entered the room, one man shouted: “You’re a snake, you’re a liar.”

He was drowned out repeatedly until he came close to losing his cool and confronted his accuser. “Come on, come on. Really? Are you going to respect the people in this room? If not, you need to leave,” he said.

The police were called in to eject the prime minister’s noisiest critics, but the heckling continued throughout, as if a number had been drinking on an empty head.

Trudeau’s willingness to tolerate the abuse was indicative of his tendency to take political risks – as he did when he fought Sen. Patrick Brazeau; as he did when he decided the Liberals would campaign on running deficits in 2015.

He was in deeply hostile terrain.

Even a question from an elderly woman who initially addressed him as “my handsome, precious one” ended up with him on the receiving end of criticism for supporting a pipeline that “could destroy our coastline”.

Trudeau should be commended for saying much the same in the face of a belligerent audience as he said in Alberta the day before. “We will be moving forward with the Kinder Morgan pipeline,” he said, explaining it was part of the government’s plan to balance the environment and the economy. “That is the nature of the compromise we have taken in the best interests of the country.”

It would be fair to say the reception was about as warm as if he’d asked the audience in Edmonton for a round of applause for his father.

It was a bold performance but that makes it all the more curious why the prime minister has not backed up the rhetoric with a promise to act.

The B.C. government has said it will restrict the transportation of bitumen until there are further studies on the impact of spills.

Rachel Notley, the Alberta Premier, has pointed out that this is unconstitutional and has threatened to retaliate by suspending discussions on the purchase of electricity from B.C. Jason Kenney, the provincial Opposition leader, has mused about a blockade to stop oil flowing to B.C.

Alberta’s case was bolstered this week by a new report from the C.D. Howe Institute that suggested oil and gas producers are struggling to stay competitive with U.S. companies because of lack of pipeline capacity.

Yet, Trudeau’s line that he doesn’t want to “opine on disagreements between provinces” is nonsense.

By making the case he did in Nanaimo, he is clearly siding with Notley and her contention that the federal government has approved Kinder Morgan and the B.C. government has no jurisdiction.

If the NDP/Green government in Victoria does not back down, Trudeau must use his constitutional power to declare the Trans Mountain pipeline a work for the general advantage of Canada under the Constitution Act, a move that would remove the authority of provincial and municipal governments.

It would be a bold political move for the prime minister – the Liberals would lose seats in British Columbia as a result. But, in truth, he has already picked which side he is on. On Friday, in Nanaimo, he looked his critics in the eyes and explained why the pipeline was approved by Ottawa – and what measures the government has taken to mitigate spills.

It was display of control and political skill.

But real leadership requires him to take the next step and head off a brewing national unity crisis by making it clear that new delaying tactics will not be tolerated.