More than just another ominous catch-phrase from war in the Big Sandbox, Black Sunday was the day in April 2004 when units of America's 1st Cavalry Division saw their routine deployment turn into a harrowing and costly fight. Enraged, motivated, and well-armed insurgents crammed the alleys, streets, and buildings of Sadr City. In that fight, a surging mob of militants ambushed one small unit of the Black Knight battalion. The heroic rescue attempt...