The failure of Great Britain and the United States to attack directly the Nazi extermination of the Jews remains an issue of controversy. This fine collection of essays-supplemented by some 40 essential documents-emerged from a joint symposium by the Air and Space and Holocaust Museums. The authors disagree sharply-one historian regards the notion that the Allies could have usefully bombed Auschwitz as "Monday-morning quarterbacking," while another calls the failure to do so "a missed opportunity of monumental proportions." Collectively, the authors have assembled not only the best and most recent technical assessments but thoughtful reflections on how to judge the hard-pressed political leaders and generals of the time. The broader questions may be unanswerable, but they merit pondering nonetheless-particularly in an age that has seen its share of massacres uninterrupted by external intervention.