On September 1, 1939 - the first day of World War II in Europe - President Franklin D. Roosevelt appealed to the warring nations to "under no circumstances undertake the bombardment from the air of civilian populations." Just six years later, British and American Allied forces had carried out a bombing campaign of unprecedented might over Germany's cities, claiming the lives of nearly half a million civilians. This film examines the defining moments of the offensive that led the U.S. across a moral divide. Weaving interviews with WWII pilots and historians with stunning archival footage of the bombing and its aftermath, the program is a haunting reminder of the dilemma imposed by war's civilian casualties, a topic that continues to resonate as America enters the eighth year of fighting in Iraq and Afghanistan. Joe Morton narrates.