ONE of the most extraordinary days in the mottled history of the island of Ireland was witnessed on both sides of the border last Tuesday.

The much-anticipated and costly Saville report ... the 12-years-in-the-making inquiry into “Bloody Sunday,”a day never to be forgotten in Irish politics ... was finally published.

On that day, Jan. 30, 1972, British soldiers fired on a civil rights march in the majority Catholic area of the Bogside in Derry, killing 14 protesters.

It was a day that caused the conflict between the two communities in Northern Ireland — Catholic nationalist and Protestant unionist — to spiral into another dimension: every Irish person conscious on that day has a mental picture of Edward Daly, later the bishop of Derry, holding a blood-stained handkerchief aloft as he valiantly tended to the wounded and the dying.

It was a day when paramilitaries on both sides became the loudest voices in the conflict, a day that saw people queuing to give up on peace ... mostly young men but also women who had had enough of empire and would now consider every means necessary — however violent or ugly — to drive it from their corner.

It was a day when my father stopped taking our family across the border to Ulster because, as he said, the “Nordies have lost their marbles.” And we were a Catholic-Protestant household.

Contrast all this with last Tuesday ... a bright day on our small rock in the North Atlantic. Clouds that had hung overhead for 38 years were oddly missing ... the sharp daylight of justice seemed to chase away the shadows and the stereotypes of the past. No one behaved as expected. The world broke rhyme.

A brand-new British prime minister, still in his wrapping paper, said things no one had imagined he would ... could ... utter ....

“On behalf of our country, I am deeply sorry.”

And there was more ....

“What happened should never ever have happened,” said the new prime minister, David Cameron. “Some members of our armed forces acted wrongly. The government is ultimately responsible for the conduct of the armed forces. And for that, on behalf of the government, indeed on behalf of our country, I am deeply sorry.”

It was inconceivable to many that a Tory prime minister could manage to get these words out of his mouth. It was also inconceivable — before he uttered the carefully minted phrasing — that he would be listened to by a hushed crowd gathered in Guildhall Square in Derry, a place not famous for its love of British leaders of any stripe, and that he would be cheered while speaking on specially erected screens that earlier had been used to relay images from the World Cup.

Thirty-eight years did not disappear in an 11-minute speech — how could they, no matter how eloquent or heartfelt the words? But they changed and morphed, as did David Cameron, who suddenly looked like the leader he believed he would be. From prime minister to statesman.

Joy was the mood in the crowd. A group of women sang “We Shall Overcome.” There was a surprising absence of spleen — this was a community that had been through more than most anyone could understand, showing a restraint no one could imagine. This was a dignified joy, with some well-rehearsed theatrics to underscore the moment.

As well as punching the sky and tearing up the first “Bloody Sunday” inquiry — a whitewash by a judge named Lord Widgery who said the British troops had been provoked — these people were redrawing their own faces from the expected images: from stoic, tight-lipped and vengeful to broad, unpolished, unqualified smiles, unburdened by the bile the world often expects from this geography.

Derry is a community and these Derry people looked like guests at a wedding — formal only for as long as they had to be, careful of their dead but not at all pious. Some began to speak of trials and prosecutions but most wanted to leave that talk for another day.

Figures I had learned to loathe as a self-righteous student of nonviolence in the ’70s and ’80s behaved with a grace that left me embarrassed over my vitriol. For a moment, the other life that Martin McGuinness could have had seemed to appear in his face: a commander of the Irish Republican Army that day in 1972, he looked last week like the fly fisherman he is, not the gunman he became ... a school teacher, not a terrorist ... a first-class deputy first minister.