BELFAST

THE front line in the Northern Ireland conflict has moved from the back streets of Belfast. The weapons are no longer ArmaLite rifles and car bombs; the warriors are no longer soldiers and hooded paramilitaries. In 2014, history itself is the new front line, and the battlefields are TV studios, newspapers, social media and the courts. The warriors are now politicians whose words are as full of hate as the bullets they have replaced. The body count may be lower, but mistrust and blame are not being replaced with hope and friendship.

In April 1998, when the Good Friday peace accord was signed, dealing with the conflict’s legacy was seen as too divisive. But that unfinished business has poisoned community relations, and confronting it can no longer be postponed.

The arrest on Wednesday of Gerry Adams, leader of the pro-Irish unity party Sinn Fein (formerly described as the political wing of the Irish Republican Army), is the latest skirmish in this new war. The arrest comes after some of Mr. Adams’s former comrades accused him of direct involvement in the abduction, murder and burial of Jean McConville, a widowed mother of 10, 42 years ago. Their testimony to an archive at Boston College was supposedly confidential.

After the Police Service of Northern Ireland gained access through legal action in American courts, Mr. Adams was arrested. Sinn Fein has accused the police of political manipulation three weeks before critical local and European elections south of the border in Ireland, where Mr. Adams’s party was, according to all the polls, poised to perform well. Back in the North, the leader of the pro-British Democratic Unionist Party, Peter Robinson, has insisted that it would have been political had the police not arrested Mr. Adams.