IN THE aftermath of 9/11, terrorism experts in the US made a bold and counter-intuitive claim: the suicide terrorists were psychologically normal. When it came to their state of mind, they were not so different from US Special Forces agents. Just because they deliberately crashed planes into buildings, that didn't make them suicidal – it simply meant they were willing to die for a cause they believed in.
This argument was stated over and over and became the orthodoxy. "We'd like to believe these are crazed fanatics," said CIA terror expert Jerrold Post in 2006. "Not true... as individuals, this is normal behaviour."
I disagree. Far from being psychologically normal, suicide terrorists are suicidal. They kill themselves to escape crises or unbearable pain. Until we recognise this, attempts to stop the attacks are doomed to fail.
When I began studying suicide terrorists, I had no agenda, just curiosity. My hunch was that the official version was true, but I kept an open mind.
Then I began watching martyrdom videos and reading case studies, letters and diary entries. What I discovered was a litany of fear, failure, guilt, shame and rage. In my book The Myth of Martyrdom, I present evidence that far from being normal, these self-destructive killers have often suffered from serious mental trauma and always demonstrate at least a few behaviours on the continuum of suicidality, such as suicide ideation, a suicide plan or previous suicide attempts.
Why did so many scholars come to the wrong conclusions? One key reason is that they believe what the bombers, their relatives and friends, and their terrorist recruiters say, especially when their accounts are consistent.
In 2007, for example, Ellen Townsend of the University of Nottingham, UK, published an influential article called Suicide Terrorists: Are they suicidal? Her answer was a resounding no (Suicide and Life-Threatening Behavior, vol 37, p 35).
How did she come to this conclusion? By reviewing five empirical reports: three that depended largely upon interviews with deceased suicide terrorists' friends and family, and two based on interviews of non-suicide terrorists. She took what they said at face value.
I think this was a serious mistake. All of these people have strong incentives to lie.
Take the failed Palestinian suicide bomber Wafa al-Biss, who attempted to blow herself up at an Israeli checkpoint in 2005. Her own account and those of her parents and recruiters tell the same story: that she acted for political and religious reasons.
These accounts are highly suspect. Terrorist leaders have strategic reasons for insisting that attackers are not suicidal, but instead are carrying out glorious martyrdom operations. Traumatised parents want to believe that their children were motivated by heroic impulses. And suicidal people commonly deny that they are suicidal and are often able to hide their true feelings from the world.
This is especially true of fundamentalist Muslims. Suicide is explicitly condemned in Islam and guarantees an eternity in hell. Martyrs, on the other hand, can go to heaven.
Most telling of all, it later emerged that al-Biss had suffered from mental health problems most of her life and had made two previous suicide attempts.
Her case is far from unique. Consider Qari Sami, who blew himself up in a café in Kabul, Afghanistan, in 2005. He walked in – and kept on walking, past crowded tables and into the bathroom at the back where he closed the door and detonated his belt. He killed himself and two others, but could easily have killed more. It later emerged that he was on antidepressants.
Even Mohammad Atta, the 9/11 ringleader and the archetype of the "normal" suicide terrorist, was misunderstood. He struggled with social isolation, depression, guilt, shame and hopelessness for many years.
Experts make other mistakes too. They assume that suicidal people are easily identifiable, that they must be irrational, and that suicide terrorists are a subset of the broader population of non-suicide terrorists, who we know tend to be relatively normal.
The misconception has been further exposed by psychologist Ariel Merari of Tel Aviv University in Israel. He recently conducted psychological tests on 15 failed suicide bombers, 12 non-suicide terrorists and 14 organisers of suicide attacks, all associated with Palestinian terror groups.
When the regular terrorists were asked if they had ever considered carrying out a suicide operation, 11 of 12 said that they had not. Among the organisers, nine of 14 said no. None exhibited suicidal tendencies or had ever attempted suicide.
For the would-be bombers it was a different story. Not only had they all agreed to undertake a suicide mission, eight displayed depressive tendencies, six displayed suicidal tendencies and two of them had previously attempted suicide.
Merari's findings provide compelling evidence that at least some suicide terrorists are suicidal. My own research adds to this, documenting suicidal traits in more than 130 attackers.
Why does this matter? First of all, labelling suicide terrorists "normal" or "martyrs" is dangerous. It plays directly into the hands of terrorist leaders, allowing them to glorify suicide bombers and recruit new ones.
It also inhibits efforts to prevent attacks. From 2001 to 2010, global suicide attacks increased by more than 300 per cent. With the exception of the fence Israel built to keep Palestinian suicide terrorists out, most attempts to combat this deadliest of threats have been an utter failure. That's why we need to understand suicide bombers properly, so we can find them and stop them before it is too late.