It's a moral maze. They did well getting through it – the Government, the Opposition, the Irish parties, the former soldiers, the Paisleys, the member whose cousin had been gunned down by the IRA... Cameron was there, presenting the Saville report in the Commons with Iain Duncan Smith beside him.

Bloody Sunday – the British state covered it up and then uncovered the cover-up. That's very unusual in this world – to expose, in Mark Durkan's phrase, "the transgressions of unaccountable power" once they had been elaborately concealed. Tony Blair was given only just enough credit for commissioning the inquiry.

David Cameron represented the state on this occasion, and did so decorously, keeping his distance from the event. His generation "learnt about it rather than lived through it", he said. He was firm but not too firm, steady but not ostentatiously so; he didn't have to struggle to control his manly emotions, as one predecessor had to.

He rehearsed the report's conclusions without evasiveness. "You do not defend the British Army by defending the indefensible," he said. "There is no doubt. There is nothing equivocal. There are no ambiguities. It. Was. Wrong."

On the other hand, there was no evidence of a plan, or conspiracy to murder civilians, and he also used the words "Martin McGuinness" several times, and twice with the words "machine gun". He also had the range to talk about the £200m given to lawyers and to assert that there would never be another open-ended inquiry like this.

The Irish MPs – who live with a different experience of what politics means – found themselves centre stage for once. They have bigger voices than mainland MPs, more powerful instruments altogether. Mark Durkan recited the names of the dead of those killed on the day, their names and ages. His voice thickened and faltered occasionally but hardly so you'd notice. He hoped for "the healing of history".

Geoffrey Donaldson, from another end of the spectrum, remembered the 18 members of the Parachute Regiment who had earlier been killed by the IRA. William McCrea told us of another IRA attack which resulted in the picture of a child putting his fingers into the bullet holes in his father's body to quell the flow of blood. His question to the Prime Minister was: "How do we get closure? How do we get justice?"

Meanwhile, Gregory Campbell said the Irish state has never investigated the funding of the IRA, or its role in "acting as midwife for an organisation whose birth resulted in the murder of thousands".

They hope the report will draw a line under the experience of that day, and maybe it will. It might even be value for money if it did.

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