Last spring, the House Committee on Foreign Affairs convened a hearing on unresolved issues associated with the Northern Ireland peace process. Many Americans—even many legislators—may have been surprised to learn that there were unresolved issues. Richard Haass, the president of the Council on Foreign Relations, testified that when he agreed to chair a series of multiparty talks on the peace process several years ago, friends in Washington, New York, and even London responded by saying, “I thought this was settled.”

It’s not. As I recount in a long investigation for the March 16 issue of The New Yorker, significant tensions linger in Northern Ireland, where so-called peace walls separate the Catholic and Protestant populations in Belfast, and 93 percent of children attend segregated schools.

One major challenge, which I explore at length in the article, is how to address the many atrocities conducted by the I.R.A., loyalist paramilitary groups, and the British government during the long conflict known as the Troubles. In South Africa, after the fall of Apartheid, a truth and reconciliation process was created to establish a historical record of the excesses of a dark era. In Northern Ireland, there has been no such comprehensive tabulation, and, as a result, many of the worst war crimes of the Troubles remain shrouded in mystery, with victims’ families uncertain who it was that murdered their loved ones, or (in some cases) even where they were buried.

This sense of irresolution was on full display in the testimony at the House hearing, which featured remarks by Geraldine Finacune, whose husband, the human rights lawyer Patrick Finacune, was murdered in 1989 by loyalist paramilitaries who were colluding with the British government.

“You’re talking about crimes that took place thirty years ago,” Rep. Dana Rohrbacher (R-CA) said at one point. “I hope we’re not just picking at scabs here.”

It is an understandable concern, and there are many in Ireland (and among the thirty-five million Irish Americans in the United States) who believe that the surest way for Northern Ireland to move into the future is to let go of the past. But the level of injury on all sides of the conflict, and the prevailing sense that there has been no accounting, represent a formidable obstacle to real progress.

Without creating some mutually accepted process for addressing Troubles-era atrocities, Haass said, “You would never form the scab. . . . You would never get to the point of healing.” As the Irish Republican leader Gerry Adams has found in recent years, refusing to address the past in some Panglossian hope that it might just stay buried is not a long-term strategy.

And the consequences of this folly could be devastating—not just for political figures such as Adams, but for the society at large. In the judgment of Haass, if these matters are left to fester, “violence . . . could very well re-emerge.”