Most of Jessica Stern's book looks at Islamic extremist groups like al-Qaida and Hamas and what drives them - but she also includes chapters on American Christian cults and Jewish militants.

"To begin with, it is only Islamist terrorists today that are causing major threats to international security," she said. "But I wanted to include the other religious traditions, because at different points in history, every religion has produced significant armies of religious killers. There is nothing unique about Islam."

In her face-to-face interviews with Islamic, Jewish, and Christian radicals, Ms. Stern finds some common themes that transcend religious affiliations.

"Almost every individual that I spoke with had strong views about globalization, and saw globalization as very threatening to identity, to an ethno-religious identity," said Ms. Stern. "And, also the feeling that global institutions like the IMF or World Bank are bad for societies, for identity. To [radical] Christians, they are seen as literal manifestations of the anti-Christ. For al-Qaida, they're seen as instruments of American hegemony."

Another common theme is a sense of humiliation and marginalization. "I think that that is a very important factor, the feeling of humiliation which a [terrorist] leader can strengthen or in some cases can help to construct; the desire of the follower for a new identity with greater dignity, more honor and the way a leader can persuade the follower that the way to achieve that new dignified, honorable identity is through violence," she added.

Ms. Stern believes, for example, the increased sense of humiliation among Palestinians is responsible for the proliferation of young teens who are willing to become suicide bombers.

"I gradually came to realize that it really is about these repeated small humiliations that seem like nothing to the Israelis, but in the end give Palestinians a sense of sheer hopelessness and humiliation, which really assist Hamas and Palestinian Islamic Jihad in their recruitment drives," explained Ms. Stern.

Terrorist leaders often set themselves up as spiritual leaders, like Osama bin Laden, and offer spiritual and monetary rewards and the possibility of a better life. In Pakistan, for example, Ms. Stern says radical religious schools and orphanages have become a breeding ground for religious warriors.

Christian cult leaders in the United States, she adds, often cut their followers off from the outside world and ban discussion of alternative views.

Harvard University lecturer Jessica Stern says terrorist leaders in the Muslim world now manipulate the simmering hostility toward the U.S. occupation of Iraq as a rallying cry that confuses politics and religion.

"I think the administration did not take on board the notion that the image of Baghdad occupied by U.S. troops and tanks was so deeply humiliating and could be used as a rallying cry for extremists, not just in Iraq but all around the world, and recruitment is up as a result," she said.

So, what will it take to combat what Ms. Stern calls a seductive idea rather than a military target?

"Sometimes a military response is required, I want to make that clear," she acknowleged. "But that is the part of war on terrorism that we are relatively good at. Also, on law enforcement and intelligence cooperation, I think we have made a lot of progress."