The top commander of NATO and Justin Trudeau have something in common: They've both believe that the "root causes" of radicalism need to be understood.

"This is a long-term, not a short-term, fight," NATO's Gen. Philip Breedlove told CBC's "The House" of the U.S.-led fight against the Islamic State.

"Until we have addressed the root causes of these kinds of issues, we can expect to have to deal with these kind of issues."

To address the causes, Breedlove said, the West must help bring health, security and jobs to vulnerable areas.

Breedlove's interview echoes comments made by Justin Trudeau in April 2013, shortly after the Boston Marathon bombings. He also drew attention to the "root causes," and his comments immediately became attack ad ammunition for the Harper government.

Trudeau, in an interview with the CBC's Peter Mansbridge, said that it is important to fully understand what drives people to terrorism.

"We have to look at the root causes," Trudeau said. "Now, we don't know now if it was terrorism or a single crazy or a domestic issue or a foreign issue. But there is no question that this happened because there is someone who feels completely excluded."

The Conservatives jumped on the Liberal leader's remarks, blasting him in an attack ad that asked "How can you make excuses for terrorists and keep Canadians safe? Justin Trudeau. He's in way over his head."

Prime Minister Stephen Harper also criticized Trudeau's comments.

"When you see this type of violent act, you do not sit around trying to rationalize it or make excuses for it or figure out its root causes," he said.

"You condemn it categorically, and to the extent you can deal with the perpetrators, you deal with them as harshly as possible."

The Conservative government, now, is doing a little bit of both. Canada has sent six CF-18 jet fighters to Iraq and is engaged in airstrikes against the Islamic State.

At home, it has commissioned studies looking into the factors that lead to terrorism. The Kanishka Project, a five-year, $10-million initiative that was announced in 2011, "will invest in research on pressing questions for Canada on terrorism and counter-terrorism, such as preventing and countering violent extremism."

The studies will cover issues like "psychology, social psychology and counter-terrorism" and the links "between research on the social psychology of the internet and on violent extremism"

The government said that these studies are different from Trudeau's comments.

"They are looking at ways in which we can obviously prevent and pre-empt terrorist acts. I think there is a difference, " Justice Minister Peter MacKay said, according to the CBC.

Jason Tamming, spokesperson for Public Safety Minister Steven Blaney, told the Huffington Post Canada in October that, "Unlike Justin Trudeau, our Conservative government will not make excuses for those who engage in terrorism."

"While we believe that prevention and intervention are important, ultimately our security, law enforcement, and military personnel will degrade and destroy any terrorist threat," Tamming said.

- With files from Michael Bolen

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