ON THURSDAY, August 10 my family and I arrived at Heathrow airport to take a flight to New York. Unlike thousands of other people that day, we made it to our destination, albeit a bit delayed. Our inconvenience was limited to four hours wait, and not being able to take my book on the plane.

It was from the US, with its own security obsessions, that we tried to follow the story as it developed back in Britain. First there were the cloudy details of the plans for a “mid-air massacre” involving many planes like the one we’d travelled on. Gradually the people who had been detained assumed names and garbled identities. As ever they were described by friends as being hypernormal people, incapable of acts of suicidal destruction, or by more sceptical neighbours as being recently devout and suddenly and strangely bearded. Then the whole thing became sub judice.

That, of course, didn’t stop the uninformed speculation about why the alleged acts had been planned, the question being still the essential one: why do some people in our country want to blow up planes and trains and buses full of their fellow citizens — none of whom has ever done them any harm?

One danger of over-schematising any answer to such a question is that it confuses like with unlike. The recent Palestinian film Paradise Now followed the short careers of two suicide bombers and, however you regarded their actions, they seemed to have plenty of direct motive to be involved.

But what about a lad from Yorkshire or a student from the Home Counties? What direct experience would lead them to similar acts of destruction? One word is particularly popular, not least with clergy: alienation. It’s ubiquitous: you can add practically anything you like to “alienation” — youth, race, poor schooling, poverty, unemployment, dislike of materialism, rejection of sexual mores — yet it still absolutely fails to explain why this person will think it right to explode other people, and all the other “alienated” (by now comprising a good half of the population) won’t. The comedian Jackie Mason once had a great skit entitled “Why Don’t Jews Rodeo?” to which I could add another: “Why don’t black lesbians blow up buses?” Aren’t they alienated enough?

But the most popular explanations of all are the most fundamentalist. A Mr Richard Riddle expressed one pole of this view so perfectly in the letters page of The Guardian that I’ll simply quote him. “We have destroyed Iraq, we are well on the way to destroying Lebanon,” says Mr Riddle, extending the “we” a little here. “Yet young British men still want to blow planes out of the sky . . . Could it be that they are a violent manifestation of many people’s view of British, US and Israeli foreign policy?”

No, it couldn’t, really. It’s one thing to throw a placard stick at a copper, Mr Riddle, it’s another to bring down a 747 full of families. Which brings me — unexpectedly perhaps — to the book I couldn’t take on the plane, but found time to read in New York. Truman Capote’s In Cold Blood, as many readers know, is a 300-page study of a crime and the two men who committed it. In 1959 Perry Smith and Dick Hickock entered a farmhouse in Holcomb, Kansas, and murdered a farmer, Herb Clutter, his wife and their two teenage children. Though robbery was the ostensible motive, the couple had, it seems, planned all along that there should be no witnesses left alive, while making sure that everyone in the house would indeed be a witness. The prospect of the killings, therefore, seem to be more important to them than the robbery.

How would you explain Smith and Hickok, the two small-time criminals and drifters who became murderers? They were called the “dark side” of affluent postwar America, and they were inevitably described — even then — as “alienated”.

Capote, in a sustained work of journalism, met them many times and explored who they really were. And they were different. Smith best fitted the profile of the alienated. He was half native-American, his mother was a drunk and a prostitute, his older brother committed suicide, his sister died after falling out of a window. Only one sibling survived to have a “normal” life. Smith also felt that he was brighter than most other folks and somehow entitled to something better. Dick Hickock, however, seemed to have a very different experience. He was white, and came from a solid farming family. He was bright, too. If he was alienated, it would have had to have been for entirely different reasons.

Obviously one characteristic they had in common was a lack of real sympathy. As Smith put it: “I thought that Mr Clutter was a very nice gentleman. I thought so right up to the moment that I cut his throat.” Another characteristic that recurs throughout the book is their constant feeling of envy, a sense of lost entitlement, without any real notion of their own responsibility for their predicaments. And a third is their sense of self-pity.

Towards the end of the book, as we prepare for the couple’s execution, Capote quotes at length from a 1960 study published in The American Journal of Psychiatry that dealt with Smith and Hickock among others. The authors wrote: “The most uniform and perhaps the most significant historical finding was a long-standing, sometime lifelong, history of erratic control over aggressive impulses.” The self-images of the killers were “as physically inferior, weak and inadequate. The histories revealed in each a severe degree of sexual inhibition. To all of them adult women were threatening creatures . . . All of them too had been concerned throughout their early years about being considered ‘sissies’.” And all had suffered “severe emotional deprivation in early life”.

Richard Reid fits almost all these criteria. The barrister Peter Herbert visited the unsuccessful 2001 shoe-bomber in prison in the United States. Reid, a former mugger, described to Herbert his desire to blow up the plane in purely political terms. Specifically, “the foreign policy of the US Government, which . . . had resulted in the murder of thousands of Muslims . . .”. But Reid was not born a Muslim, and his parents weren’t Muslims, nor did he come from a Muslim community. When he did convert in prison, he embraced the most extreme form he could find. “The sermons of [Abu] Hamza and others,” says Herbert, “gave him a greater understanding of how to interpret his faith in a way that supported the use of violence. It also reinforced his view about the scale of US aggression . . .” Reid, in other words, was violence in search of a cause, not the other way around.

Perry Smith and Dick Hickock had never killed anyone before they met in jail. Together they made mayhem and murder seem normal. Prison helped, by surrounding them with a culture in which indifference towards the victim was — of necessity — the natural stance. Just as now the internet provides a place for paedophiles to congregate and wish each other luck in getting jobs in children’s camps. Or certain preachers or certain organisations provide a space where blowing up planes can be made to seem like a wonderful act.

Read David Aaronovitch’s blog here

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