The first World War was the first modem industrial war. In this war, machine guns, tanks, aircrafts, chemical weapons were used on a massive scale.Millions of soldiers were recruited from around the world and were brought to the front inships and trains.About 9 million civilians died and 20 millions were injured.Most of the killed and injured were men of working age, reducing the able-bodied workforce in Europe.During the war, industries were reconstructed to produce war related goods.Britain borrowed large sums of money from US banks. Thus, the war transformed the US from being an international debtor to an international creditor.