There can be no escaping recriminations after yesterday’s disgraceful scenes in Dublin. Michael McDowell, the republic’s justice minister, must establish quickly what preparations the Garda Siochana had made to ensure that the Love Ulster march could proceed smoothly. For their part, the gardai must identify the rioters who brought chaos and destruction to the capital’s streets. The march, organised to commemorate the hundreds of victims of the Provisional IRA’s campaign of terror in Northern Ireland, was always going to be tense. It was no secret that attempts would be made to disrupt it, and McDowell would have expected the republic’s security forces to plan for confrontation.

Once the decision had been made to allow the march, those who came to Dublin to express their outrage, anger and grief should have been able to proceed safe in the knowledge that the gardai were mobilised to ensure their safe passage through the streets. That did not happen, and the centre of the city was instead subjected to rioting, looting and the spectacle of burning cars within yards of the houses of the Oireachtas.

There can be no excuses. Dublin was not just a city for marchers yesterday: it was also going about its normal Saturday business, its streets full of shoppers and tourists, of people young and old who neither knew nor cared about Northern Ireland’s problems. They too deserved the full protection of the gardai, and they too were failed.

The Love Ulster campaign has many detractors. Its focus is narrow, its view of the north’s past and future is blinkered. Yet it represents a body of opinion in the province that the people of the Irish republic have consistently failed to understand and with which they have never come to terms. The riots, though, have shown Ireland’s political leaders that the failure to ensure peaceful progress in Northern Ireland since the Good Friday agreement carries consequences that can no longer be neatly contained beyond the border.

The anger of many members of the Unionist community at the disregard for their victims and the continuous concessions to republicans is real. Eight years after the agreement, there remains a political vacuum in Northern Ireland and no prospect of rapprochement between the two extremes. Society has become more, not less, polarised and communities live in fear of the paramilitary organisations that terrorise them. Instead of peace, the province has loyalist and republican gangsterism and an economy in real risk of collapse. The blame for that rests squarely with those elected by their people to deliver working devolved government, but who choose to live in the past. The British and Irish governments have also failed. Their refusal to stand firmly against the deceit of Sinn Fein/IRA has weakened democracy in the north and diminished respect for the institutions of government.

The riots in Dublin have brought that message of failure to the citizens of the republic. They must now realise that Northern Ireland cannot be conveniently forgotten. Love Ulster wanted to make that point yesterday. It may have been provocative, but democracy requires that everyone should be allowed to make their point, and their protest, peacefully. The marchers were failed by the gardai, and failed by the Irish state.

Bertie Ahern said yesterday: “It is the essence of Irish democracy and republicanism that people are allowed to express their views freely and in a peaceful manner.” He is stretching a point. Republicanism, Provisional style, has murdered those who dissent from its orthodoxy. That culture of violence was evident yesterday, aided and abetted by youthful thugs who enjoy throwing stones and missiles at gardai. McDowell must discover whether complacency and poor planning lay at the heart of the riots, but Irish republicans of all shades must ask themselves whether they have the capacity to understand a people who share their island, but not their beliefs.

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