To Catch a Terrorist

There's a better way to stop terrorists.

Photographer: Mark Metcalfe/Getty Images

When terrorism experts warn about the threat posed by a "lone wolf," people picture a confused young Muslim glued to his computer, growing more bloodthirsty with each beheading video he watches. Yet the man responsible for this week's hostage crisis in downtown Sydney -- Man Haron Monis, a 50-year-old Iranian and self-declared "spiritual healer" -- doesn't uphold the stereotype. If they want to prevent future attacks, authorities shouldn't, either.

The reality is that budding terrorists fit no single profile. Intelligence officials have come to downplay the idea that would-be jihadists evolve along a continuum from personal grievance to radicalization -- online or at a mosque -- to violence. Nor is there evidence that greater religiosity raises a potential extremist's risk profile; indeed, the opposite may be true.

This raises questions about the strategies police have traditionally used to try to prevent terrorist attacks -- infiltrating local Muslim communities and mosques to listen for extremist chatter, for instance. Censoring Islamist websites and taking down YouTube videos may actually do more harm than good; new online forums inevitably spring up, and in the meantime, authorities lose a potentially rich source of leads.

How can police recognize potential terrorists? Research has found that many of them exhibit a combination of specific traits. As many as 40 percent, according to a study by Ramon Spaaij and Mark Hamm, show signs of mental-health problems, as the unstable Monis did. And like Monis, many have had run-ins with the police or have amassed criminal records. (Monis was out on bail on charges going back more than a decade, including involvement in his ex-wife's murder and sexual harassment.)

Especially in recent years, many suspects have been highly active on social media before their attacks, continuing a tradition of terrorist broadcasting that goes back at least to the Unabomber's manifesto in 1995. In many cases, they have attempted contact with organized terrorist groups, even if they haven't formally joined. And at some point, obviously, all have procured weapons, bomb-making materials or both.

None of these red flags by itself offers slam-dunk confirmation of an imminent threat, and intelligence officials can't keep an eye on everyone. To bolster defenses, local police and other authorities must be trained to be alert to the full range of warning signs. They also need trust and open channels of communication within their communities -- which can easily dry up if Muslims feel they're being unfairly targeted or monitored. And authorities need to share information better with one another, so they can flesh out suspects before attacks occur. Monis was already known to Australian federal police, but he appears not to have been included on any terrorist watch list.

Worldwide, more sophisticated efforts could be made to counter jihadist narratives, whether from al-Qaeda, Islamic State or other groups. Many analysts question whether such narratives alone can inspire violent attacks. But as Australian Prime Minister Tony Abbott correctly noted, "sick individuals exist in every society." Islamic State's glossy online vision of a rising caliphate offers some of those people a chance to feel part of something larger than themselves.

How Australia's open, multicultural society responds to this week's attack can contribute to that global effort. While there are fears of a backlash against local Muslims, there are also powerful signs of solidarity among Australians of all faiths. To those who would paint the West as intent on suppressing Muslims, it's hard to imagine a more enlightened reply. 

To contact the senior editor responsible for Bloomberg View’s editorials: David Shipley at davidshipley@bloomberg.net.