High Quality Content by WIKIPEDIA articles! Germany and Poland were the main opposing forces in the Polish September Campaign. Tactics and military hardware used in the Invasion of Poland varied between the two sides; The German economy was geared toward military production which supplied their armed forces with equipment that was often superior to their Polish counterparts. Old tactics such as Vernichtungsgedanke and the concept of the Schwerpunkt combined with newly mechanized units punched holes in Polish lines and close air support provided by the world class Luftwaffe disrupted Polish supply and communications lines. Other German tactics included the targeting of civilian targets in terror bombings to inflict huge losses amongst the civilian population, sending streams of refugees out of afflicted areas, thereby hampering Polish logistics. In 1939 the German navy also had an advantage over the tiny Polish fleet.