Journalist Eyal Press is the author of "Beautiful Souls: Saying No, Breaking Ranks, and Heeding the Voice of Conscience in Dark Times."

Twenty years ago last week, Serbian snipers fired on a crowd of unarmed demonstrators in Sarajevo, launching a brutal siege that brought ethnic violence in the Balkans to menacing new heights.

In the two decades since, attention has understandably focused on the deeds of the architects and perpetrators of the Balkan wars. Confronting the truth about how the violence was planned and orchestrated, many have argued, is an essential step in getting formerly warring factions to reckon honestly with their responsibility for what transpired.

But this point should apply no less to the conduct of those who behaved honorably during the war, daring to cross the lines of ethnic division that too many of their fellow citizens chose not to traverse....