Robert Fisk: The innocent became the guilty, the guilty innocent

We knew the First Battalion, the Parachute Regiment. "Tough" was the word we reporters used if the soldiers were beating up rioters.

Brutal was the word we should have used. But sometime towards the end of 1971, I think we all realised that the Parachute Regiment was being prepared for some pretty nasty confrontations. They were the hard men, the reserve battalion at Palace Barracks, Holywood, a boring seaside town on the south side of Belfast Lough, a unit that spent most of its time waiting for trouble.

Shortly before Bloody Sunday, I'd seen them confronting a crowd of angry Protestants just off the Shankill Road. The "Prods" had blocked the street, set fire to some tyres; they were protesting at the lack of security. So the local British battalion in the Ardoyne called up the reserves and the first thing we saw was an Army "Pig" – a big armored vehicle with a wide-bodied snout over the engine – come roaring round the corner, knocking a youth clean off the road on to the pavement. It drove straight into the burning tyres and the paratroopers jumped out of the back with wooden cudgels and got to work on the street lads.

There were howls of rage and curses from the Brits and eventually the Prods cleared off and the soldiers of 1 Para stood in the street looking bored. Then a door opened and out came a man in his fifties. A Belfast Protestant, hair greying, he sort of hobbled on to the street as if he'd been hurt badly years ago and he walked right up to a group of Paras and plunged his hand into his pocket. He brought out an old Army red beret with a metal badge of parachute wings fixed to it and a tatty old regimental tie.

The soldiers watched him, bemused. Then he began to tear the beret to pieces, right there in front of the soldiers, and ripped up the tie. The man was shouting 'Bastards, bastards," over and over again at them and he dropped the ruined beret and tie at his feet and stomped on them. The soldiers laughed. And the man kept shouting "bastards" and he was crying and then he shouted at the soldiers: "I was at Arnhem."

What had happened to the Parachute Regiment? A week before Bloody Sunday, John Hume, the MP for Foyle, encountered a far more disturbing demonstration of power by the same regiment. There was a nationalist demonstration on the beaches of north Derry and the Paras had turned up and beaten the demonstrators and a Para officer walked up to Hume and – in a very English public school accent – threatened him. "I realised something new was happening," Hume was to tell me years later. "Some decision had been taken by the military. I was very worried about this. These were very hard men. There was no way of negotiating with them."

Could we have guessed what this meant? Or the libels that British journalism was to commit against the dead of Bloody Sunday in the coming weeks? As usual – and for Derry, read Fallujah or Gaza or any Afghan village where civilians get in the way – the innocent became the guilty and the guilty became the innocent. "Bordering on the reckless" – Widgery's whining description of the British Army rabble that fatally shot 14 Catholics in the Bogside – was the only real half-truth to emerge from his disgracefully short and lazy report.

They are old now, those soldiers, the same age in 1972 as those they killed in Derry. I was on The Times – the glorious, pre-Murdoch Times – and I was not in Derry on the day. But for years I went there as I go back, still, to the scene of Middle East massacres. In 1997, home from Beirut, I was again prowling around Derry. Was anything left? In the wall of a ground-floor apartment in Glenfada Flats, I found two bullet holes from Bloody Sunday, two gashes in the cheap stucco and cement to remind the Catholics of the Bogside of the power of a self-loading rifle.

"There's another hole round the corner in Chamberlain Street," a young man told me. "Would you like to see it?" Cruelly, I told him I'd seen enough bullet holes in the Middle East and the Balkans these past 22 years. "But do people know about Bloody Sunday in Beirut?" the man asked. No, I said. Not a soul there knew – or cared – what happened here. So all the man said was: "Jesus Christ!" It is a name much invoked on the Derry memorials.

The most dramatic of these is a simple granite cross erected to the memory of the 14 "murdered by British paratroopers on Bloody Sunday 30 January 1972". Beside it, back in 1979, someone had scribbled a note: "All we need is the truth to help heal the wounds."

Did we get it yesterday? Was it enough? Certainly it is more than the Palestinians will ever get for the 1982 Sabra and Chatila massacre. Or the people of Qana who were demanding an inquiry in 1996 after Israeli shells slaughtered 101 civilians sheltering in the UN compound. The UN's official report into the massacre implied that it was deliberate.

Lord Widgery was not so brave. Of 500 eyewitness testimonies given to him, he bothered to read only 15. Was he merely idle? Or was he a weak, morally enfeebled man, more fearful of condemning his country's armed forces than he was of concealing the truth?

Or did we British journalists have something to answer for in our slavish adherence to the notion of the British Army's integrity? I don't think we cared about the Irish – either the Catholic or the Protestant variety. I don't think we cared about Ireland. I don't think the British Army cared. At last, I suppose, the Saville report has answered that scribbled note I found outside the Glenfada flats 13 years ago.

But at least the people of Derry care about others who have died unjustly. In 2003, as the Americans occupied Iraq, American paratroopers opened fire on a crowd of protesting Iraqis in the city of Fallujah. They killed 14, claiming they were shot at. Subsequent inquiries suggested this was a lie. A few days later, in Baghdad, I took a call from an old friend in Derry. He wanted to lead a delegation of Bloody Sunday relatives to Fallujah, he said, to show their sorrow for the dead Iraqis. I don't think the Americans cared about the Iraqis. But the Irish of Bloody Sunday cared.