The battles for the Germans' last line of defense in World War II, including Arnhem, Aachen, the Huertgen Forest, and MetzHow German commanders made decisions under fire Built as a series of forts, bunkers, and tank traps, the West Wall--known as the Siegfried Line to the Allies--stretched along Germany's western border. After D-Day in June 1944, as the Allies raced across France and threatened to pierce into the Reich, the Germans fell back on...