My father was a great storyteller. At bedtime when I was a small child I would demand he tell me a story. My favourite stories were those about when he was a soldier in France during World War One. As I got older he added more realistic details to these stories, and I came to see how he had left his home in the Australian bush as an inexperienced young man with little education and a passion for sport and returned a committed socialist and atheist with an intense compassion for fellow soldiers whatever their nationality. He despised the generals who treated their men as no more than disposable puppets, and he hated all political leaders who started wars, and what he called 'the vested interests' who profited from war. He was one of those Andrew Carroll calls 'combat veterans' who abhor 'the glorification of war itself. They believe that sanitising or concealing its ugliness only trivialises the sacrifices made by the men and women who serve.' Dad would have wept and laughed and reminisced over this collection of letters and 'their messages to the world'.

He would have been especially pleased by the inclusion of the letter from Alfred Dougan Chater to his mother on Christmas day, 1914. Here Chater described how on the front line German and English soldiers left their trenches to talk to one another and agree that they would all have preferred to be at home. Dad often described how soldiers from both sides had kicked a ball around together, and always he would add that for the rest of the war the generals made sure that over every Christmas period the heavy guns of the artillery were in constant action.

The letters in this collection come from a wide variety of wars. Andrew Carroll wisely gives the background to each letter. Those uninvolved in such wars are often uninterested or ignorant of the conflicts, and do not want to be reminded of the repeated futility and cruelty of war.

The experience of war changes people, and not for the better. I became used to Dad's obsession with not wasting food and with his closest friend's wheezy breathing, a legacy of the mustard gas used in the World War One. When I went to Sydney University in 1948 the majority of my fellow students were ex-service men and women, most of whom had had what we used to call 'a bad war'.

They would have understood what US Private Al Puntasecca meant when he wrote to announce to his family his return from the Korean War. He said, 'You know, it's almost funny, we see a guy in a wheelchair, a guy on crutches, one arm, hooks for hands, and, we break our backs trying to help him. But, what about the wounds you can't see? The phantoms, the nightmares, the ghosts in your head? I am going to tell you now, you'll need lots of patience with me. Patience, and, understanding. We all will. See you soon. See you soon. See you soon.'

And what of the children caught up in war? Galia, a young girl in Leningrad during the siege, writes to her aunt to tell her that each member of her family, one after the other, has died and she is all alone, under fire from the Germans and starving. 'Dearest Aunt Natasha my hope now rests with you and I wait for you to come like a guardian angel. I think that you will not abandon me.' But Aunt Natasha did not come and no one knows what happened to Galia.

Suffering, whether physical or mental, becomes unbearable if no one acknowledges that we suffer. If someone says, 'I see that you are suffering and that is terrible' somehow our pain lessens. We may fear death, but if we can assure ourselves that some important part of us will continue on, be it in our children, our work, or just in the memories our friends hold of us, somehow death becomes more bearable.

Our greatest fear is that the person that we are will vanish like a rain drop in the ocean and no one will bear witness to our existence. Behind the Lines does much more than educate us about the prevalence and evil of war. It allows us to bear witness to the life and suffering of those who otherwise might be forgotten. If we bear witness to others, then perhaps others will remember to bear witness to us.