Soon after George W. Bush came to office, eight years ago, he told a confidant that “there’s no Nobel Peace Prize to be had” in Israeli-Palestinian diplomacy. He turned his attention instead to places farther east in the Middle East, with mostly horrific results. But, as Obama told his listeners at AIPAC last June, there remains the Talmudic imperative of tikkun olam, “the obligation to repair the world.” In four years, or eight, he may well have won no Nobel medal, made no final repair. But the obligation of constant engagement is deep; the cost of negligence is paid in blood. And, what is more, history has proved that the seemingly impossible can be achieved: the Irish and the English have all but resolved a conflict that began in the days of Oliver Cromwell, and on January 20th an African-American President will cross the color line and move into the White Housea house that slaves helped build.