Image caption Researchers say this study gives clues to how suicide attacks could be averted at the last minute

Suicide bombings have become the defining act of political violence of our time.

From Afghanistan to Madrid, London to Sri Lanka, they are an all pervasive presence in our political landscape and a crucial tactic employed in modern day terrorism.

As the inquest into the 7/7 London bombings tries to piece together the events of that day, little research has ever been done on the minds of suicide bombers themselves.

Trying to discover exactly why a suicide bomber would kill themselves to further an apparent cause is, for obvious reasons, an impossible task.

But one study from Tel Aviv University has endeavoured to find out if suicide bombers shared any noticeable personality traits or characteristics - by interviewing and analysing would-be suicide bombers.

These were men who had attempted to carry out a suicide attack but had failed for a variety of reasons, including technical defects (the bomb did not go off) or capture (either on the way to the target or earlier).

Some of our suicide bombers actually got to their target and pressed the switch Professor Ariel Merari, Tel Aviv University

They discovered a pattern of being unable to handle stressful situations, an inability to see the bigger picture and a tendency to be intimidated by people in positions of authority.

Meanwhile, the organisers - responsible for commanding and co-ordinating suicide bombings - had bigger egos, were better equipped mentally to handle stress and, for the most part, were unwilling to consider a suicide attack themselves.

Intimate access

Retired professor and world-renowned terrorism expert Ariel Merari had access to 15 would-be suicide bombers being held in jail for attempted attacks relating to the Israeli-Palestinian conflict.

Five of the group were sent by Hamas, five by the Palestinian Islamic Jihad and five from Fatah's al-Aqsa Martyrs Brigades.

In addition to this, Professor Merari and his team interviewed the organisers of suicide attacks - all from the same groups.

Alongside the organisers and failed bombers were a control group - 12 men who had been tried and jailed for various political violence activities from stone-throwing to armed assaults.

The first challenge for Professor Merari's team was in convincing subjects to speak. The prisoners insisted on getting the backing of higher-ranking members of their organisation.

"I told them why we wanted to carry out this project, this study," explained Professor Merari on Radio 4's All in the Mind.

"There was real lively discussion. In the end they agreed to participate and that was indeed the key to achieving the consent of the other organisers."

In recent years, global suicide attacks have increased. Between 1981 and 2000, 17 countries had been the victim of suicide attacks, compared to 32 between 2001-2008.

Suicide attacks are often tied to a perception of religious fanaticism from the perpetrator.

However, this latest research suggests religious significance ranked lower than other factors when the prisoners made their decision to carry out a suicide attack.

"Almost all of them were religious, but the suicide guys were not more religious than the control group members.

"The depth or intensity of religious belief was not something which distinguished them from other non-suicide terrorists."

'Afraid'

Instead, Professor Merari found that "national humiliation" ranked higher as a reason for an attack.

"This was by far the clearest, strongest motivation they expressed.

"It is not a matter of personal suffering; they tried to avenge their communities suffering. They mentioned events that they saw on television, not events that happened to them personally."

The men interviewed as part of the organisers group were, on average, older, better educated, and, perhaps predictably, unlikely to put themselves forward for suicide attacks.

"Nine of 14 admitted that they would not be willing to carry out suicide attacks themselves - because they were afraid," said Professor Merari.

Any kind of impediment, statistically, would increase the chance that the would-be suicide bomber changes his mind on the way to the target. Professor Ariel Merari, University of Tel Aviv

"They did not use the term 'afraid', but they use terms such as 'not everybody can carry out an act such as this', 'it takes a special person' etcetera.

"The remaining five said 'In principle I would be willing to carry it out, but my role as a commander was more important and therefore I did not do it'. They were frank, I guess, in giving this straightforward answer."

The study also noted that the organisers' portrayal of suicide bombers as being "highly determined youngsters" was misguided.

"The suicide [bombers] themselves gave a very different picture. Sixty-six per cent of them admitted that they were afraid, they hesitated, and when we looked at larger number of suicide cases we found that 36% of 61 cases of suicide bombers the candidates just dropped out."

'Close as possible'

Prof Merari acknowledges that because his subjects all "failed" their mission, the study can not given an exact representation of a suicide bomber.

However, his team believes that their findings are as "close as possible".

"Some of our suicide bombers actually got to their target and pressed the switch - just that the bomb they were carrying failed to explode because of mechanical failure.

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"Psychologically, these are suicide bombers for all effects and purposes."

His findings conclude that measures can be taken to prevent attacks based on the common personality traits.

"One of the conclusions of this study was that any impediment on the way to the target increases the chance that the suicide bomber would change his mind. This is because those who hesitate need some sort of excuse.

"They have to have some sort of excuse to keep their self-respect.

"Any kind of impediment, statistically, would increase the chance that the would-be suicide bomber changes his mind on the way to the target."