Pictures of the beach near Mullaitivu, the last outpost of Tamil Tiger resistance in Sri Lanka, would have been among the greatest visual images of what war does to people. They would have been, if anybody had been there to take them.

Those pictures don’t exist. The Sri Lankan Government has been amazingly successful at keeping people away from this conflict and, as a result, appalling atrocities have been committed.

There is always a need to be a witness to conflict. When the war in Sri Lanka started 25 years ago I went to Trincomalee to cover it. Journalists are usually good at getting into places where they are not wanted, but not on this occasion. Nor at any time since. This has been an invisible war.

That beach on the Indian Ocean will be a bloodbath. Families have been sheltering without food or water in holes dug in the sand, subjected to shelling for days. A doctor in the area has spoken of thousands of bodies lying unburied and the “stench of death” hanging over the war zone. For the victorious soldiers there is always the temptation to take revenge for friends killed earlier in the conflict.

Some of our most powerful images of war are from beaches. Think of the photography of Eugene Smith, war correspondent for Life magazine, who witnessed the American offensive against Japan during the Second World War. Or Robert Capa’s images of battle from the Normandy beaches.

We have nothing like this to tell us what has happened in Sri Lanka — a Buddhist country, a place that teaches us to live in peace. It is a tragedy to see war tear apart its people like this.

Governments around the world are getting more savvy about excluding journalists from war zones. The US Government partly blamed its failure in Vietnam on the freedom of the press rather than on its military strategy. That led to me being banned from reporting the Falklands war. I had dinner recently with some senior military men from that time who said “we missed you”. There are no images to remind them — and us — of what happened.

In Iraq and Afghanistan it has been convenient for governments to keep journalists away from the front line. It was in pursuit of some real pictures of the Iraq war that poor Terry Lloyd and his cameraman were killed.

I am 74 now and I have been watching this conflict in Sri Lanka unfold with the same horror I felt 50 years ago. We cannot afford to be shielded from what people do to each other in war.

Don McCullin has produced a new book for Reporters Without Borders, which fights for press access

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