The total cost of the war has been set at $337,980,579,657. The total dead reached the staggering figure of 13,000,000, with an additional 28,000,000 casualties. In hindsight the majority of commentators have concluded that it was all in vain. The First World War introduced killing on an unprecedented scale, it gave the world the carnage of trench warfare and the extra dimension of fighting in the air. But the war had not made the world safe for democracy. The war to end war had not been fought. Instead, it led only to an intensification and a multiplication of problems. The 1920's saw the collapse of most of the economies of the world, followed by depressions and the rise of dictatorships in the 1930's. Then came World War II, which in reality was only an extension of the First World War. The decades since have seen only a continuation of wars, depressions, international tensions and anarchy on an ever-increasing scale.