New York City, 1968: a Jewish community under siege. Rising antisemitism was rupturing black-Jewish relations. Shifts in the Democratic Party threatened longstanding Jewish political alliances. Assimilation was undermining Jewish religious observance. Into this cauldron of political and religious turmoil stepped the remarkable Harold M. Jacobs. The son of an immigrant peddler, Jacobs was the classic interwar Jewish success story, overcoming personal...