Assault in Norway: Sabotaging the Nazi Nuclear Program By Thomas Gallagher. By 1942, German scientists seemed to have an insurmountable head start over their Allied counterparts in developing an operational atomic bomb. Allied hopes of stalling the Nazi nuclear program rested on sabotaging a fortress-like factory where "heavy water" was produuced and stockpiled. A suicidal mission by any estimation. But a brave team of Norwefiam exiles, trained in Britain by Special Operations Executive, infiltrated their homeland. And after hiding in the frozen wilds and eking out existence, they launched one of the war's most daring commando raids. Gallagher here recounts in vivid detail the planning and execution of Operation Gunnerside.