Book excerpt: Germany's opening run of victory in World War II was only made possible by the panzer forces that Heinz Guderian (1888-1954), the father of modern tank warfare, had created and trained, and by his audacious leading of those forces from 1939-1941. Guderian's breakthrough at Sedan and lightning drive to the Channel coast virtually decided the Battle of France. The drive he led into the East came close to producing the complete collapse of Russia's armies, but at the end of 1941 Guderian was dismissed for taking a timely step back instead of pandering to Hitler's illusions. He was recalled to service only when Germany's situation had become desperate, and was eventually made Chief of the General Staff when it had become hopeless.