Daniel Hannan is an MEP for South-East England, and a journalist, author and broadcaster. His most recent book is Why Vote Leave.

Irish citizens tend not to commemorate the formal moment of their independence, and who can blame them? The Government of Ireland Act of 1920 was, by most measures, a failure. Unpopular on both sides of the border, it ended up provoking two civil wars: a short and intense one in the Irish Free State, a sporadic and protracted one in Northern Ireland. Nor does the subsequent evolution of the Free State into a sovereign republic offer a single heroic date that might be termed independence day.

Instead, Irish patriots mark the Easter Rising of 1916, a moment wrapped in high-flown language, admirable ideals and melodrama. I don’t use the word “melodrama” lightly. Many of the leaders were playwrights, and some wore stage uniforms throughout the insurgency. Some passers-by, seeing handsome young men striking poses at the General Post Office, assumed that they were involved in some new theatrical venture.

Dublin is celebrating the centenary in all manner of ways, some moving, some beautiful. The bravery with which the mutineers died, and the explicitly sacrificial, even paschal, way in which they saw their deaths, appeals to something in the Irish soul. “I die that the Irish nation might live,” said Seán Mac Diarmada, one of the leaders, as he faced the firing squad. And live it did: from his death came a kind of resurrection. At Easter, such feelings are powerful – more so, perhaps, in Ireland than in other places.

It could so easily have been different. But for the unbelievably heavy-handed response by the authorities, the Easter Rising might now be remembered, not as the birth of a nation, but as a slightly opéra bouffe interlude.

How many rebels were involved? It’s hard to say: some people later claimed to have been “out” at the GPO when, as the joke of the time had it, they were really out buying stamps. Most historians reckon that there were between 1000 and 1400 active participants. By way of context, the 16th Irish Regiment suffered 4330 casualties in just three days at the Somme six months later.

In one sense, it was the First World War that catalysed the insurgency. Many Irishmen had signed up in 1914, responding to appeals by the Nationalist leader, John Redmond. While most of those volunteers wanted autonomy, few wanted total severance. Republican leaders were uneasily aware that, once large numbers of veterans came home having served under the Union flag, the dream of a wholly separate state would be over. They knew they needed to act swiftly

It’s odd how perceptions of the two conflicts have shifted over the past century. The First World War, which enjoyed almost unanimous support at the time, is now regarded as futile to the point of criminality. The Easter Rising, by contrast, was seen by most contemporaries as irresponsible and pointless, but is now recalled as Ireland’s greatest moment.

Why? Mainly because of the brutality with which troops, coarsened by the Western Front, responded. Dublin was treated, not as a British city, but as a rebel outpost to be bombarded. As a stunned George Bernard Shaw later observed: “All that was necessary was to blockade the Post Office until its microcosmic republic was starved out and made ridiculous. What actually happened would be incredible if there were not so many living witnesses.” As the ringleaders were taken out and shot in batches, public sympathy swung toward them and, by association, their ideas. Republicanism went from being a fringe doctrine to, by 1918, something very close to a settled position.

The exaltation of the men of 1916 created a powerful idea in Irish politics, namely that a group of idealists without an electoral mandate or any other kind of authority might take direct action and then be retrospectively legitimised by events. That creed has a lot to answer for. It sustained the IRA and other terrorist gunmen through decades of political violence.

It is hard to read the history of Britain and Ireland without wanting to weep at the missed opportunities. For more than a century, Westminster had played catch-up in its Irish policy, always addressing a previous problem. By the time religious equality was proclaimed in 1829 (something Pitt intended as a parallel to the 1801 Act of Union) the argument had moved on to land reform. By the time the government began to address landlords’ abuses, the argument had moved on to Home Rule. By the time Home Rule finally got through Parliament, the argument had moved onto independence.

Yet even by 1916, it was not inevitable that the blood-dimmed tide would be loosed. A modicum of sensitivity at Westminster might have seen the Easter Rising fizzle out, and the delayed 1912 Home Rule Act implemented after the war. Ireland might have evolved peacefully into a self-governing Commonwealth ally – rather as, say, New Zealand did. How many guns might have been silenced, how much sorrow stopped up?

It has taken us a century to reach what ought to be the natural state of amity between two peoples alike in language and law, custom and kinship. In the process we went through the estrangement of the Second World War and the horror of the Troubles. Although ordinary people stubbornly maintained their habits of intermixture and intermarriage, the two governments saw their relations deteriorate to the point where, in 1969, the Irish Cabinet was discussing whether to send troops in anger across the border.

And for what? Simply to get to the present arrangement, where kindred peoples share an archipelago with mutual respect? Surely there were swifter and surer routes. “Was it needless death after all?” asked Yeats. Yes. That’s what makes it so unutterably sad.