Our divisions and resentments run deep, and we hunger for peace and healing. Yet we push fault and blame across to the other side. All are complicit in the sins of the world, yet there is no justice without specific wrongs being accounted for. The imperfect lesson that history teaches us is that peace and reconciliation are only possible when there is penance and mercy

More than 500 years ago, there was a violent land, where bloodshed both political and personal spilled not only in alleys but in the public squares. This was a land of booming commerce and crushing debt, where the rich retreated to high fortified towers while prisons filled with the poor. The people of this place were almost all Christians, and yet their ­religion brought more division than peace.

This was medieval Italy: vendettas, tavern brawls, papal interdicts. Even the origin of the political conflict between Guelfs and Ghibellines was attributed to a vendetta murder on Easter Sunday, at the foot of a statue of Mars. My home in the United States may seem far from this time. We now learn of Guelfs and Ghibellines mostly to read Dante, and forget their grievances as soon as we’ve learned them. But this violent, commercial, idealistic and unequal world shared many of my own country’s troubles; and can offer some guidance for those who hope to make peace here.