A video of the scene from Monday's Boston Marathon bombing showed people running toward the wounded, trying to help. A flood of support and sympathy poured out all across the Internet. And Bostonians rushed to donate blood and offer spare bedrooms to those displaced by the blast.

Even though a human (or humans) caused the carnage at the finish line, such acts of kindness, as well as a sense of empathy, are actually hard to overcome — even for the terrorists, psychologists say.
"A whole industry of propaganda is aimed" at convincing potential terrorists that their intended victims are worthy of death, said Arie Kruglanski, a psychologist at the University of Maryland who has researched the roots of terrorism. [History of Human Aggression: 10 Ways Combat Has Evolved]

"Part of the ideological persuasion to get them to do these things is to reduce the humanity of the victims," Kruglanski told LiveScience. "So the victims are perceived not as other human beings, but rather as vermin, as subhuman creatures."

Quest for significance

Two bombs — reportedly stuffed with ball bearings, BBs and headless nails as shrapnel — exploded Monday (April 15) just before 3 p.m. EDT near the finish line of the Boston Marathon. At least 176 people were wounded, and three killed, from the blast. Among the fatalities was 8-year-old Martin Richard, who was waiting for his father to finish the race. Richard's mother and sister were reported as seriously wounded. There are so far no suspects in the bombing.

Terrorists do not fit into a simple mold, said John Horgan, the director of the International Center for the Study of Terrorism at Pennsylvania State University.
"There's no profile, there's no personality, there's no checklist and there is no silver-bullet solution that helps explain why and how people become involved in terrorism," Horgan told LiveScience.

However, there may be some common psychology necessary to carry out such an act, Kruglanski said.

"The underlying motivation is what we call a 'quest for personal significance,'" he said. "They try to do something important, either because they feel insignificant on their own … they were humiliated in some way, or their group was denigrated."

While some people respond to feelings of powerlessness and insignificance by turning to humanitarian aims — becoming a peace activist, for example — would-be terrorists draw on violent ideologies. Violence is a quick shortcut to feelings of significance, Kruglanski said.

"Violence enjoys this very clear advantage, that by striking, by shooting, by exploding a device, a very simple action immediately makes you out to be a significant, heroic kind of person," Kruglanski said.

View of victims

In this worldview, the innocent victims of a bomb are subhuman, at worst, and incidental, at best. Timothy McVeigh, whose 1995 bombing of a government building in Oklahoma City killed 168, famously described the 19 children who died in the blast as "collateral damage."

"For a person who engages in this kind of activity, the immediate victims are meaningless. They're simply a means to an end," Horgan said. [Science of Terrorism: 10 Effects of 9/11 Attacks]

It's hard work maintaining that belief. Horgan, who has interviewed nearly 200 terrorists around the world, said some eventually come to feel remorse for the innocent lives they took. But especially in the moment, many "work very hard to convince themselves that what they've done is righteous."

Though stories of violence may dominate the news, there's good scientific evidence to suggest that humans are wired to care for others. By toddlerhood, children take it upon themselves to be helpful, for example. Even 6-month- and 10-month-olds prefer helpful characters over mean ones, studies suggest. As adults, we quite literally feel others' pain. A study published in January in the journal Molecular Psychology found that when doctors see their patients in pain, the pain-processing regions in their own brains activate.
It's easiest for terrorists to reduce their guilt when they choose a method like a bombing, so they don't have to be nearby to see the damage they've done, Horgan said.

Preventing terrorism

Although it is a major goal of both the United States and the United Nations, terrorism is hard to pre-empt, because terrorists don’t fit into one demographic profile, Kruglanski said. Radicals tend to speak their minds, making them easy enough to identify in the community, Kruglanski said, though not all of those radicals would ever turn to terrorism in any case. Detention centers and prisons also run de-radicalization programs for suspected and convicted terrorists.

Typically, these programs run along two lines: direct and indirect, Kruglanski said. A direct approach would be to confront the terrorist's belief system. In the case of an Islamic terrorist, for example, clerics might come in to explain how fundamentalist interpretations of the Koran are flawed.

This "dialogue" approach can work, Kruglanski said, but not for terrorists, who are very firm in their beliefs, or for leaders who don't appreciate criticism of their interpretations. In these cases, an indirect approach can sometimes help. The goal of these programs is to give a radicalized individual something else to live for, whether a vocation, art or even spiritual practices, such as yoga, Kruglanski said.

"It directs their attention from these collectivistic goals and on to their individualistic lives," he said.

Measuring whether you've prevented someone from participating in terrorism in the future is a difficult task, Horgan said, but it's important to remember that even among radicals, most people won't resort to violence — though terrorists rely on the randomness of their acts to make civilians feel like they or their loved ones could be next.

"The way in which we're talking about the nature of the threat, the way in which we talk about this as some sort of existential problem, I think we need to be very, very careful to avoid that," Horgan said.

"The fact of the matter is, this is a very low-probability event," he said. "We should never, ever lose sight of that."