That is a question Colleen Bell asks students in her International Terrorism class, and the answers are pretty consistent: to protect family, to defend one's country, to defend a clear threat to one's core values.
"Most people are not truly pacifists, in the sense that, ‘there are no conditions under which they would use violence,'" said Bell, assistant professor in the Department of Political Studies.
Bell's exercise is to make a point that terrorism, and those that practice it, are not "madmen, they hate us, they hate our freedom." Terrorists are rational, often even well-educated people.
"What I think is important in the study of terrorism is you actually have to have some empathy for the people that you're trying to analyze— and by empathy, I don't mean sympathy," she emphasized. Rather, by looking at their own rationales, we can better understand what drives those who commit heinous acts.
But what is "terrorism" and what makes a person a "terrorist?" Political studies and international studies lecturer Martin Gaal explained the term has no legal definition, despite decades of attempts by the United Nations and the League of Nations before them. There are good reasons for the ambiguity.
"It's a way to turn a freedom fighter into … well, even ‘criminal' seems to be higher on the pecking order than ‘terrorist,'" he said. "It seems when you get the label ‘terrorist,' you get put on the list of the lowest of the low, people without morals, without conscience, without humanity."
The label can also change with circumstance, Gaal said, citing the mujahideen in Afghanistan in the 1980s, who were backed and funded by the West while they were fighting the former Soviet Union.
"They were the freedom fighters, they were the good guys, but as soon as they were no longer on our side, we cut off support, they turned against us, and now they're terrorists."
For states, the "terrorist" label is a useful one, Gaal explained, as it allows governments to define their adversaries as an existential threat—that is, attacking a society's very values and way of life. That kind of a threat "allows the state to do extraordinary things, even extra-legal things."
Examples include invoking the War Measures Act to respond to Canada's October Crisis in the 1970s, and creation of new legislation such as the controversial Bill C-51, which would extend Canadian anti-terror laws.
Other consequences of terrorist attacks are the creation of new security organizations such as the Department of Homeland Security in the United States and Public Safety Canada, or actions such as high levels of electronic surveillance of the public in the U.K.
It is ironic that while the word "terrorism" is now used to elicit public acceptance of such actions, the word itself was coined to describe malfeasance by the state against its citizens.
"Historically the word ‘terrorism' originated in the French Revolution and the Reign of Terror," Bell said. "That was precisely a state practicing terror against its own population or elements of the population who were believed to be undermining the revolution."
Both Bell and Gaal agreed that although the "terrorism" label can be arbitrarily assigned, the word does describe specific tactics—that is, extreme violent acts that elicit fear in a population to achieve some political goal. It is a set of tools popular with groups that have no hope of beating their adversaries in open combat on a defined battlefield.
"The violence itself is actually a demonstration of weakness," Bell said. "Tactics undertaken are hit-and-run, they're surprise. The adversaries involved have no capacity to beat those whom they oppose."
Hence, terror: make a population so afraid that they demand their leaders stop what they are doing or otherwise capitulate. Does it work? It depends on the definition of success, said Bell, citing the example of Spanish troop withdrawal from Iraq war after terrorists bombed commuter trains in Madrid.
Then, there is 9/11, which had impact far and beyond the thousands killed in the event itself.
"Osama bin Laden would have argued 9/11 was very successful because it engaged the U.S. military in a conflict it could not win," Bell said. She explained that in the 15 years since New York's Twin Towers fell, tensions throughout the Middle East have proliferated; the "War on Terror" has been a bust.
The roots of terror remain and these too have common themes.
"There's usually some sort of wrong or perceived wrong that the group wants to have righted," Bell said.
She cites examples such as the Tamil Tigers who were born in response to persecution of the Tamil minority by the Sri Lankan government, a similar predicament to Russia's Chechen separatists.
For extremist groups, religion can actually be a distraction: there are always political objectives, such as overthrowing a government, claiming territory and power. Religion is simply a flag to rally around, and scriptures are cherry-picked and interpreted to support these political objectives.
"When we focus on religion, we can lose sight that there are underlying politics," Bell said. "It distracts from what they're trying to achieve politically and that's never reducible to simply religious terms."
So how big of a threat is terrorism? Acts of war waged by nation-states have killed and continue to kill far more people than terrorist attacks. Those attacks, stoked by sensationalist media, shock the public psyche, but the real impact is slight.
"There's that famous meme going around that more Canadians are killed by moose than by terrorists," Gaal said. "I had that on my door for a while."
There is a fine line between freedom and safety, and Gaal questions whether Canadians need to sacrifice access to personal information, freedom of movement and other traditional liberties on the altar of security.
"To what degree are we prepared to relinquish our rights and freedoms?" he asked. "I don't think we've come to that point yet in Canada."