TORONTO – Liberal Leader Justin Trudeau says it was Prime Minister Stephen Harper’s “ego” that led him to send six CF-18s to participate in airstrikes in Iraq, rather than a concern for Canada’s long-term interests.

Two weeks ago, the Conservative government decided the CF-18s would join the international coalition fighting the Islamic State of Iraq and the Levant (ISIL) as well as two surveillance aircrafts and one in-air refueler. Trudeau refused to back the government’s combat mission in Parliament, saying Harper had not made the case for war in Iraq and that, as a result, Canada should only engage in non-combat roles such as training of Iraqi and Kurdish fighters, medical support, logistical support or expanded humanitarian and refugee support.

At the time of his announcement, however, Trudeau overshadowed his own speech by telling an on-stage interviewer: “Why aren’t we talking more about the kind of humanitarian aid that Canada can and must be engaged in, rather than trying to whip out our CF-18s and show them how big they are?”

In an interview with The Huffington Post Canada Monday to promote his new book “Common Ground,” Trudeau suggested he doesn’t regret his controversial comment.

“People in the room appreciated it,” he said.

Trudeau explained he is a “fairly outspoken” person. “When I get passionate or worked up about an issue I say things that the Conservatives and opponents and critics like to pounce on,” he said.

Trudeau said he is very confident the Liberal party took exactly the right position on ISIL.

“As the months unfold I am certain that Canadians will realize that the Prime Minister did not think about Canada’s long-term interest or even what Canada has best to offer in the fight against ISIL when he made his decision, and it was more about ego.”

The Conservative party released a new attack ad online Monday with several torqued, out-of-context quotes and attributions saying Trudeau isn’t up to the job of being prime minister because of his “whip out our CF-18s” joke.

Trudeau, 42, told HuffPost he originally thought he’d run for party leader after serving some time as a cabinet minister in someone else’s government and had “earned my chops” – but circumstances changed his original plan.

Would he have benefited from the additional experience? Trudeau said he hasn’t wasted time thinking about it. “Woulda, coulda, shoulda? No.”

He said the drawback of trying to do politics by being “authentic” and “being yourself” is that opponents will always take “any small comment and magnify it and amplify it,” and “you start second-guessing yourself.”

“I just truly believe in the fundamental democratic principle that this is me, I think I can do a good job leading this country forward,” he said.

Talking about openness and transparency, he acknowledged several passages in the book could also be used against him, such as his admission his former roommate was years later convicted of child pornography. He also paints a picture of himself as a smart but undisciplined student and someone who, on a few occasions, demonstrated a sense of entitlement.

People who like him will vote for him, he said, and those who don’t won’t. Trudeau said he won’t “pretend to be something I am not.”

“The Conservative attack room would love nothing more than for me to start robotically reading scripted lines like the Conservatives do,” he told HuffPost.

“I’ve made the commitment to Canadians that I’m going to stay myself and I’m going stay open about it and I’m going to make sure that the thoughtfulness with which I approach issues continues to shine through.”

Trudeau told HuffPost he supports bombing ISIL and U.S. airstrikes, but he just thinks Canada’s resources could be better used in non-combat roles.

“The argument hasn’t been made that Canada is best served in participating in air strikes, and as all the experts say, at the end of the day ISIL will only be defeated by local military boots on the ground, and I think that’s what we have to focus on supporting.”

In his conversation with HuffPost, Trudeau defended his decision not to use his autobiography to propose policy prescriptions for the country.

“Common Ground” focuses on Trudeau’s early life at 24 Sussex, his parents’ messy divorce, his mother’s battle with mental illness, his relationship with his father, his awkward teenage years, and early adulthood on the West Coast. His marriage to wife Sophie Gregoire, his decision to get involved in politics and later his decision to run for a seat in Parliament and then the Liberal leadership are also covered. While the book spends time discussing the problems with the Liberal party, and how Trudeau believes the Conservatives have divided Canadians rather than unite them, it offers mostly broad statements for a better Canada.

Trudeau said the book is not meant to be a policy handbook but a “piece of the process” on the road to giving Canadians a reason to vote for him.

“If I am going to be asking people to entrust me with a really important responsibility next year, I feel it’s important to share the path, the process, the experience that I took that informs a vision for this country,” he said.

As far as the policies, he said, they will come.

“I’ve staked an awful lot of very, very strong policy positions and I will continue to,” he said, referencing his support for abortion rights, Canadian unity, the Keystone pipeline and legalizing marijuana.

“But the document that will lay out an electoral platform is called electoral platform, and that will be put out at election time.”

He told HuffPost he believes the next election will be about how best to help the economy using the surplus that may – or may not, if the Tories offer up large tax cuts – be there. While the Tories are going to offer tax relief, Trudeau said he is more interested in investing in infrastructure, education, and other ways that can grow the economy to create better jobs for more Canadians.

He pledged to reverse the Tories’ promise to expand income-splitting to couples with children under 18, adding he would even look at reversing other promises such as the doubling of the children’s fitness tax credit which is scheduled to come into effect next spring for the 2014 fiscal year.

“We are going to evaluate every different proposal as it comes forward and make a determination about whether or not it actually helps Canadians or not,” he said.

“We need to see what the Liberal platform is in its entirety and we do not yet know what kind of fiscal situation the country will be 12 months from now when the election hits,” he added.

Canadians, Trudeau said, could be convinced to accept a tax hike if it means a better economic plan.

“The Conservatives are notorious for looking at electoral advantage in the policies they put forward, we are not looking at that,” he said.

“We are looking at what is in the best interest of Canadian families and that is the lens that we going to hold.”

Trudeau told HuffPost he is amazed by how much of the Tories’ legislative agenda and energy is now devoted to attacking him and to winning the next election, scheduled for Oct. 19, 2015.

“They’ve stopped even pretending to be trying to govern the country for its best interest, everything they do is about winning the next election,” he said.

Monday, the federal government announced the beginning a new campaign designed to discourage marijuana use with teens. The ads are widely believed to be a way for the Tories to use public funds to target Trudeau’s policy on legalizing pot. The College of Family Physicians of Canada, the Canadian Medical Association and Royal College of Physicians and Surgeons of Canada refused to sign off on the anti-marijuana advertisements from Health Canada in August saying the ads had become “a political football."

The million-dollar ad buy is scheduled to run for seven weeks on television until December.

The Conservative party also launched a website attacking him for embracing tax hikes.

And last week, a leaked cabinet memo confirmed the Tories’ plan to change the copyright laws to allow political parties to use news content in political ads, even if it’s against the wishes of the news organizations that created the content.

Trudeau said he won’t use attack ads or personal attacks but will offer plenty of strong contrast between Harper and his opponents that “won’t be nasty and negative.”

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