On the battlefield most wounds are usually hideously obvious. Shattered limbs, spilled guts, gashed heads are all part of the rollcall of the physical damage that can be done by modern weaponry. The aftermath is also apparent even though modern medical technology has done wonders in providing prosthetic devices which give mobility and dignity to those who have lost limbs in action. But spare a thought for the hidden wounds that no one can see - the trauma that comes from being under fire and the problems triggered by the experience.

That is the subject of this intelligently written and agreeably unsensational study by Matthew Green, a seasoned journalist with experience of reporting from recent combat zones in Iraq and Afghanistan. There is a term for the syndrome. It’s known as post-traumatic stress disorder or PTSD and thanks to the high tempo of operations undertaken by our armed forces in recent years it has received a good deal of publicity.

Once upon a time it was known as “shell shock” or “lack of moral fibre” and the use of that terminology suggests that it was a shameful condition, that those suffering from it were unable to cope with the dirty business of warfare and were therefore lesser beings. Thankfully that stigma has been reduced and today’s armed forces are more aware of the problem, although as Green makes clear it has not disappeared completely. One of his interviewees, a military policeman suffering from PTSD, remembered a sergeant from another regiment saying that he had “a full platoon of weak people who say they’ve got PTSD – they need to man up and get on with the job.”

This is a world away from the experience of military charities such as Combat Stress which deals with the problem of PTSD and whose director of medical services Dr Walter Busuttil is a leading expert. What makes Green’s study so important and so timely is the fact that during his research he was given full access to the charity’s ground-breaking work (I write as a former trustee). At the same time he is not blind to its shortcomings and the criticisms voiced by other health-care professionals.

Under Busuttil’s direction a new six-week programme was put into effect working in conjunction with the National Health Services and this is having an effect at a time when the number of referrals has been increasing and will go on increasing as veterans come forward for treatment. It’s not perfect not least because many of those who are ex-forces have existing problems such as drug and alcohol addiction and are not always susceptible to treatment. Known as “lager therapy” this form of self-medication only exacerbates mental problems and Green cites the case of Mark Connolly, a young Scots veteran who survived an operational tour in Afghanistan only to be killed in a drunken brawl in Germany.

It’s never easy to encourage people to discuss such matters but Green has done just that. All too often the veterans have been so traumatised by the actions that triggered PTSD that revisiting the time, the place and the circumstances can be damaging but Green has clearly worked at the problem. One of the many strengths of this nuanced book is the sympathy and compassion he brings to the experiences of soldiers such as an unnamed sniper tormented by what he witnessed on the front line who reached the brink but recovered a degree of quietus that enabled him to get on with his life. In that respect Green also makes the point that not everyone returning from the front is a ticking timebomb.

Many more, the majority, come back unscathed and in support of his contention Green quotes Dr James Treadwell a criminologist at Birmingham University who makes the not unsurprising claim that former service personnel are “more likely to explode because they were unemployed on the estate drinking in the pub.” In other words, PTSD has wider social ramifications than simple survival from the battlefield.

Only now are the military authorities taking the problem seriously and Matthew Green’s revealing and thought-provoking study is a timely and much-needed addition to a subject which is not going to go away any time soon.