The NDP leader is coming out swinging at Justin Trudeau, whose existence he's barely acknowledged until now.
Last April, on the eve of Trudeau's coronation as Liberal leader, Mulcair dismissively batted away questions about the threat the third-place party's popular new messiah might pose to the NDP's newfound claim to be the government in waiting.
"My job is to replace Stephen Harper's Conservatives," he told CBC's The House.
Five months later, that's still Mulcair's goal. But with the Liberals continuing to hold the lead in opinion polls and New Democrats languishing back in their traditional third-place slot, Mulcair can no longer afford to wait in hopes that Trudeau will blow himself up or that his extended honeymoon will finally peter out as the novelty wears off.
"We're going to take on Stephen Harper. He's our adversary for the next campaign," Mulcair said in an interview as he prepares for a caucus retreat next week to plot strategy for the fall.
"But we're also going to talk straight up with Canadians about the fact that we're the only one who can be relied on to actually make things different."
And that necessarily means deflating expectations of Trudeau — in particular, zeroing in on his perceived weakness when it comes to managing the economy.
Trudeau gave his rivals an opening last week, when he resolutely refused to be rushed into pronouncing detailed policy prescriptions for what ails the economy. He said he intends to consult extensively with Canadians before developing a platform for the 2015 election.
Mulcair likened Trudeau's stance to short-lived prime minister Kim Campbell's infamous assertion that election campaigns aren't the time to talk about complicated policy issues.
"That's the Kim Campbell approach, right? You know, this is far too serious to talk to you about in advance," he scoffed in an interview.
Mulcair's allusion to Campbell — who soared to record highs in the polls after her election as Progressive Conservative leader in 1993, only to crash and burn in an election a few months later — was doubtless deliberate. At any rate, it's clear he hopes Trudeau will follow a similar trajectory.
At the NDP's annual summer caucus retreat last year, Mulcair said he warned his MPs that the NDP's honeymoon, following his own election as leader six months earlier, would not last.
"Our (poll) numbers were very high and they were giddy with the numbers and I just sat everybody down, literally all 100 MPs and I said ... 'Take a deep breath, those numbers aren't going to hold, the Liberals are going to go through a year where it's their turn to have a leadership race, they'll get a lot of attention, they'll be on helium at the end of the spring session.'
"This is not unexpected to me. But there's an arc to these stories, there's a cadence to them. And what we're seeing now is for the first time ... some people are just scratching their heads and saying, 'What's this? You mean you're not going to have any ideas and you're expecting us to just let you coast until the next election?'
In contrast to Trudeau's reluctance to be pinned down, Mulcair said the NDP will spend the fall setting up the economic themes it intends to push during the 2015 campaign: household debt, credit card fees, seniors in poverty and inter-generational equity — his belief that "we're leaving the largest ecological, economic and social debt in history on the backs of the next generation, which for the first time in Canadian history is going to have less than the generation before."
"And that's something we're not just going to talk about, we're going to prescribe how we can change things."
In some respects, Mulcair faces the same challenge as Trudeau: the need to prove his economic bona fides. Having never formed government federally, he acknowledges Canadians are wary of handing the NDP the keys to the national treasury.
But unlike Trudeau so far, Mulcair has taken pains since becoming leader to stress his background as a prudent public administrator and has attempted to send reassuring signals about his economic policies, such as adopting a more open posture toward free trade deals and repeatedly stressing that provincial New Democrat governments have a better record of balancing budgets than any other party.
"It's not a very sexy campaign theme to say you're going to provide good, competent public administration but it is something that we have to talk about ... we're going to have to be dealing with that straight up," he said.
Mulcair's newfound willingness to engage battle with Trudeau doesn't mean he intends to let Harper off the hook.
The prime minister has delayed the return of Parliament until sometime in October, when he hopes to hit the re-set button on a scandal-plagued year with a mid-mandate throne speech. But the NDP leader, who won rave reviews for his prosecutorial questioning of Harper on the Senate expenses scandal during the spring, doesn't intend to let Harper change the channel without a fight.
The NDP will continue to hammer away at what Mulcair describes as Harper's implausible insistence that he knew nothing about his former chief of staff's decision to give Sen. Mike Duffy $90,000 to reimburse the Senate for invalid living expenses — a transaction now at the centre of an RCMP investigation.
"He can run but he can't hide," Mulcair said.
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