The former head of the Central Intelligence Agency is cautioning Canadian officials to keep in mind the delicate balance between security and privacy when crafting new laws.

In an interview with CBC Radio's The House, retired U.S. general and former CIA director David Petraeus said that balance should be at the heart of an open and transparent debate.

"The general thrust of this always has to be, again, to strike that proper balance between taking measures that, at the end of the day, are in some cases intrusive, that is what surveillance is all about after all, and yet allow the freedoms as much as is absolutely possible, to the citizens of a country that prides those freedoms greatly," he said.

Following the tabling this week of a bill that would give the Canadian Security Intelligence Service more powers, the government has promised that there's more security legislation coming. Already, critics, including Canada's privacy commissioner, have warned the government not to go too far.

"Getting that balance right between protection and freedoms is always difficult, emphasis will shift back and forth a bit based on recent experiences," Petraeus said.

The architect of the so-called U.S. "surge" in Iraq in 2007 says it's too early to say whether Canada's role in fighting the Islamic State of Iraq and Syria (ISIS) will make the country more of a target, or lead to more radicalization.

Petraeus also said that he believes ground troops will ultimately be needed, but not necessarily Western troops. "I believe in the case of Iraq that very clearly they should be the Iraqi security forces," he said.

'Terrorist' act?

Petraeus said he doesn't believe the attacks in Ottawa and Saint-Jean-sur-Richelieu represent a larger threat to Canada. "I tend to think that in many cases there are distinct individual motivations in situations like this," he said. "So, I think until we actually understand better what was going through the mind of these individuals when they carried out these terrorist acts, it would probably be unwise to generalize about them."

The use of the word "terrorist" caused political waves in Ottawa this week.

Prime Minister Stephen Harper labelled what happened in Ottawa last week a terrorist act. But NDP leader Tom Mulcair has a different take.

"I don't think we have enough evidence to use that word," Mulcair said this week. "When you look at the history of the individual involved you see a criminal act, of course. You see something that was meant to provoke the type of reaction that we had," he said.

"Frankly the information that is now available to the public comforts me in my choice not to use the word terrorism in describing the act," he said. "That's our point of view. That's my point of view."

For Liberal leader Justin Trudeau, there was no need to raise such questions. "The RCMP was clear: these were acts of terrorism," he said.