Most Americans know U2's song "Sunday Bloody Sunday." It's a highly recognizable piece of music, and the song's been popular ever since they wrote it. But most people in this country who at least can sing along with the chorus simply have no idea what the song's about. If they've seen a live performance of the anthem, they may be dimly aware that frontman Bono is adamant that "this is not a rebel song," without truly grasping what he's talking about. Not a rebel song? Um, OK, Bono, sure, just sing it for us, OK?

Bono is adamant about the song he wrote, because, as he put it during a performance in 1982: "For a long time I have been... frightened... frightened about writing a song about where I live... the place I live... Ireland and its problems... this is called: 'Sunday Bloody Sunday'... this is not a rebel song...." Bono was frightened that his song would become a rallying cry, and lead to more death. Because, while "bloody" is inexplicably a "bad word" in British English, the song's title is in no way metaphorical. It describes an event which took place in 1972. A bloody event. And Bono's fears were that singing about it would just lead to more of the same -- which is why he cries "I'm so sick of it!" during most live performances of the song. Because the song is a plea for peace, and decidedly not a rallying cry to arms.

Irish history is rather depressing to study, since it is so cyclical in nature. The Irish people have been desperately fighting invaders and occupiers for longer than written history has existed on the island. While this occasionally led to minor victories, mostly it led to crushing defeats, and the execution of the rebel leaders. Over and over and over again. This seemingly endless cycle is exactly what Bono's sick of.

Recent Irish history (using a much more European definition of "recent," since this goes back hundreds of years) has been a struggle against the island being occupied by England. And, true to the cyclical nature of Irish history, what happened in 1972 was the third Bloody Sunday in this history. The first happened in 1920, and involved the Irish Republican Army in Dublin, during Ireland's War of Independence. This was the original I.R.A., not the more modern incantation (which is properly called the "Provisional Irish Republican Army," or P.I.R.A., or just "Provos" for short), comprised of the grandchildren and great-grandchildren of the original I.R.A. As I said, cyclical. The second Bloody Sunday took place in Belfast a year later, in 1921.

The third one -- the one Bono was mostly writing about -- took place on January 30, 1972. But while the first two involved actions in an ongoing war, this Bloody Sunday took place during a civil rights march. Twenty-six unarmed protesters were shot by British Army troops on the streets of Bogside in Derry (in Northern Ireland, the part of the island which did not gain independence in the earlier war).

The reason this is all in the news this week is because of the release of a British report by an inquiry formed to examine what happened. This, it should be pointed out, is the second official inquiry into the incident, but the first can be discounted because it was nothing more than a whitewash, hastily released just after the event had happened.

The conclusion of the inquiry is truly stunning news. This inquiry was the most expensive Britain has ever undertaken, costing hundreds of millions of pounds. It was begun in 1998 by Prime Minister Tony Blair, responding to pressure from the families of the casualties who wanted the truth to come out.

Twelve years later, the truth did come out -- this week. From the findings of the inquiry:

The firing by soldiers... on Bloody Sunday caused the deaths of 13 people and injury to a similar number, none of whom was posing a threat of causing death or serious injury.... The immediate responsibility for the deaths and injuries on Bloody Sunday lies with those members of Support Company whose unjustifiable firing was the cause of those deaths and injuries.

It further states that the British soldiers "lost control" and shot civilians in the back who were trying to escape the deadly fire. Civilians were shot trying to aid those who had already been hit. The soldiers lied about what happened afterwards, saying the crowd were throwing Molotov cocktails and stones at them (which they weren't). The British soldiers shot without giving any sort of warning, at unarmed men and boys. The commanding officer either disobeyed orders or wildly overstepped his authority.

As I said, this is pretty stunning stuff. And not just for the events described, either, but for the very fact that the inquiry happened at all. It is impossible to draw parallels in the American experience -- the closest I can think of would be if we now opened an investigation (which would take 12 years and hundreds of millions of dollars) into the shootings at Kent State in 1970. The sheer improbability of American politicians today approving such an investigation is what I am talking about when I say the British inquiry into Bloody Sunday is stunning -- by its mere existence.

Even more stunning was the British Prime Minister standing up in Parliament and apologizing. Once again, it's hard to put this into perspective for an American audience. The BBC has the full transcript of David Cameron's speech, but it is so extraordinary that I had to include a long excerpt:

Mr. Speaker, I am deeply patriotic. I never want to believe anything bad about our country. I never want to call into question the behaviour of our soldiers and our army, who I believe to be the finest in the world. And I have seen for myself the very difficult and dangerous circumstances in which we ask our soldiers to serve. But the conclusions of this report are absolutely clear. There is no doubt, there is nothing equivocal, there are no ambiguities. What happened on Bloody Sunday was both unjustified and unjustifiable. It was wrong.

Lord Saville concludes that the soldiers of the support company who went into the Bogside did so as a result of an order which should not have been given by their commander. He finds that, on balance, the first shot in the vicinity of the march was fired by the British Army. He finds that none of the casualties shot by the soldiers of support company was armed with a firearm. He finds that there was some firing by Republican paramilitaries but none of this firing provided any justification for the shooting of civilian casualties. And he finds that, in no case, was any warning given by soldiers before opening fire.

He also finds that the support company reacted by losing their self-control, forgetting or ignoring their instructions and training and with a serious and widespread loss of fire discipline. He finds that despite the contrary evidence given by the soldiers, none of them fired in response to attacks or threatened attacks by nail or petrol bombers. And he finds that many of the soldiers -- and I quote, "knowingly" -- put forward false accounts to seek to justify their firing. Lord Saville says that some of those killed or injured were clearly fleeing or going to the assistance of others who were dying. The report refers to one person who was shot while crawling away from the soldiers. Another was shot in all probability when he was lying mortally wounded on the ground. The report refers to the father who was hit and injured by army gunfire after going to attend to his son.

For those looking for statements of innocence, Saville says that the immediate responsibility for the deaths and injuries on Bloody Sunday lies with those members of support company whose unjustifiable firing was the cause of those deaths and injuries. Crucially, that, and I quote, "none of the casualties was posing a threat of causing death or serious injury or indeed was doing anything else that could, on any view, justified in shooting."

For those people who are looking for the report to use terms like murder and unlawful killing, I remind the House that these judgments are not matters for a tribunal or politicians to determine. Mr. Speaker, these are shocking conclusions to read and shocking words to have to say. But Mr. Speaker, you do not defend the British Army by defending the indefensible.

We do not honour all those who have served with such distinction in keeping the peace and upholding the rule of law in Northern Ireland by hiding from the truth. There is no point in trying to soften or equivocate what is in this report. It is clear from the tribunal's authoritative conclusions that the events of Bloody Sunday were in no way justified.

I know that some people wonder whether, nearly 40 years on from an event, a prime minister needs to issue an apology. For someone of my generation, Bloody Sunday and the early 1970s are something we feel we have learnt about rather than lived through. But what happened should never, ever have happened. The families of those who died should not have had to live with the pain and the hurt of that day and with a lifetime of loss.

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.

I have to say, it takes a lot of political courage to make a speech like that, in such a public venue -- especially since David Cameron's only been in office for a month. Which is why I use the word "stunning." It's hard to imagine an American politician making a speech like that, for any reason, in any circumstance. This report exonerated the victims of this tragedy, thirty-eight years after the fact.

Ireland is a different place today than it was back in 1972. Or when Bono wrote his song (which came out in 1983). U2, for a long period, refused to even play the song, and they've only ever played it in Northern Ireland twice. More recently, however, they have started performing the song again, as time distances Ireland from the period they call "the Troubles."

The band knew the song would be interpreted and used in ways they really didn't want it to be. The first line in the song was reportedly originally: "Don't talk to me about the rights of the I.R.A., U.D.A." but was changed to the much less inflammatory: "I can't believe the news today." Which was probably a good decision, since the song's message is a cry for peace, and not a call to arms.

And while the report just released in Britain might not fully answer the plaintive question posed repeatedly in the song's lyrics ("How long? How long must we sing this song?"), it certainly goes a long way towards closing the book on this tragedy.

Maybe this cycle in Irish history can finally be broken, in other words. No violence happened as a result of the announcement of the report's conclusions. A sense of relief and closure and exoneration prevailed instead. There was no call to arms. There was, instead, a peaceful rally. Which is where this particular historical cycle started. So maybe now Bono can stop having to explain that "this is not a rebel song," and rather than feeling he must sing the song... maybe now he can just sing it to please the crowd who wants to hear an old favorite. One can only hope.

Cross-posted at The Huffington Post

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-- Chris Weigant