He pointed out he has actually done something about the Senate. NDP Leader Tom Mulcair, he said, is promising to abolish the Senate, something that is not in his power without opening up the Constitution.
And Prime Minister Stephen Harper, he reminded his audience of Liberal supporters at their Montreal convention, promised to never appoint a senator, and then named 57 of them.
Trudeau, of course, cut loose his Liberal senators a few weeks ago by kicking them out of caucus and telling them to sit as Independents. "That," he said, "is how you make change happen."
"For me, Mike Duffy is not worth another Meech Lake," said Trudeau, referring to the failed and divisive agreement that would have reformed the Senate by altering the Constitution.
Anyone who appointed Senators Duffy, Pamela Wallin and Patrick Brazeau, said Trudeau, should be careful about making judgment a campaign issue, referring to the Conservatives' attacks on retired lieutenant-general Andrew Leslie's $72,000 taxpayer-funded moving fees.
Leslie is one of Trudeau's advisers and a likely candidate for a Liberal nomination in an Ottawa riding.
Trudeau spoke about themes he has covered before — a growth economy, open trade, a robust environmental policy — without offering any detail about how his party might make reforms or changes.
But he spoke broadly and at times eloquently about a kind of Liberal philosophy.
Speaking softly, and not often in French, he bookended his talk with an anecdote about "Nathalie," a middle-class soccer mom who worries about debt and her children's future.
In the end, he rounded out Natalie's story with a question about whether she has seen her lot improve under Harper. "Does Nathalie have more confidence in her future?"
At one point, he exhorted the audience not to think of the "Conservative base" as enemies. "As all of you know, the 5.8 million Canadians who voted Conservative aren't your enemies. They're your neighbours." He described them as "good people" who have been let down by Stephen Harper.
Trudeau went even further and painted Harper as a "young idealistic reformer" who had been a "principled man." None of these remarks seemed designed as punch lines to elicit applause from a compliant audience, but Trudeau carried on before pulling out the rapier.
Harper, he said, has abandoned his principles over his eight years as prime minister, and he lambasted him for changing his tune on income splitting, even though, Trudeau pointed out, the policy is a bad idea.
He described Harper as having thrown his own idea "under the bus" after realizing it might not help him get elected — an example, Trudeau said, of Harper forgetting a basic sense of fairness.
Trudeau warned his audience to be prepared for attack ads, because he said, "Conservatives get a little nutty about me."
He mentioned some of the policies being presented at the convention and did not avoid listing one about assisted medical death. "We Liberals," he said as a preface to his statement about the terminally ill, "will always be on the side of personal freedom."