This was often called the first time Blitzkrieg was tried on the battlefield, though similar methods had been used before. The German surprise attack was successful. It was very effective against the ineffective and demobilized Polish Army, whose tanks and airplanes were nearly out and mostly old. They were outflanked, outmaneuvered, and outnumbered in September 1939, and easily destroyed by the Blitzkrieg. The Poles, if well prepared, could have had two million soldiers in the fight.