Audacity to Believe, is Sheila Cassidy’s fine and moving memoir of her time as a young doctor working in Chile. During that time the US organised a bloody coup against the democratically elected president, Salvador Allende, which brought to power the despotism of Margaret Thatcher’s close friend, General Augusto Pinochet.

Cassidy was herself caught up in the terror that Pinochet unleashed upon his own country. After having treated a wounded rebel she was betrayed, arrested and tortured.

Cassidy is forensic in detailing what happened next, and her descriptions are chilling. She describes two sessions of electric shock torture to the most sensitive areas of her body. In the first session she made up a story about who put her in contact with the rebel she treated. Having wrung this story from her she was dressed and put in a car with the secret police who took her to check out her story. Having found it a farrago of lies they brought her back, stripped her naked again and resumed the torture. This time she broke and told her torturers everything they wanted to know.

There is a common practical, as opposed to moral, objection to torture, which is that, as Cassidy attested, a person being tortured will tell their torturer anything to get the torture to stop. So it is difficult to know what is true, and what is false. However as Pinochet was under no existential threat after he seized power the cowards and rapists of his secret police had plenty of time to check the stories of their thousands of victims and bring them back to the torture chambers if the original stories proved false.

In war, or under the proverbial ticking bomb situation where time is of the essence, it is considerably less likely that torturers would have the luxury to test the accounts of each of their victims. At least until now.

In his book The Finish, about the assassination of Osama Bin Laden, Mark Bowden provides some detail of how the information technology of US defence and intelligence services has advanced in the years since the slaughter of the 11th September attacks on the Twin Towers. The result of this is increased capacity for rapid analysis of data from mass surveillance and cross-checking of interrogations, including those obtained under torture. In other words we are moving into a world in which the intelligence and defence communities of the US, and much of NATO presumably, can render obsolete the practical objections to mass surveillance and torture.

 This is a distressing prospect for a number of reasons. As Mark Bowden has shown elsewhere, in his book Roadwork, the permitting of even limited provision for torture can lead to much wider acquiescence in it as a routine practice. This inevitably comes to ensnare the manifold innocent along with the fewer guilty, and can become a deep source of alienation from and resentment of the perpetrators. As the lessons of Abu Ghraib prison showed the violence of torture will inevitably give rise to the violence of insurrection, as torture not only corrodes the souls of the perpetrators and erodes any of their claims to moral superiority, but instills in its victims a burning desire for revenge.

We seem to be moving into a time when Orwell’s prediction of a permanent state of war is becoming true. In part this has arisen from a glib attitude amongst Western leaders towards war, an ignorance of the political contexts in which they have meddled and an abject failure to understand the political implications of the violence they have unleashed, which has included the incarceration, mistreatment and torture of thousands who have been swept up in these wars.

The erosion of practical constraints on torture increases the risk that in some future conflagration military and political leaders will be enticed by the promise of it delivering some easy tactical advantage. It is vital that they remember that one of the political implications of this form of violence is that it will sow dragon’s teeth that may blossom as armed men in years to come.