No, there won't be any world war. Countries don't have enough funds for war economy. + There is no need for world war today. Your argument is totally invalid.
Both World Wars were during times of economic hardship, with the roots of World War 2 in particular being notoriously economic as a result of the first World War. When war breaks out, it gives fractional reserve banks a "leverage as much as you want and get away with it free" badge. Additionally, society (who ultimately evaluates the real value of a currency) will actually forget traditional market economics and psychologically create a "stay" on inflation as seemingly unlimited funds flow into the market. If you remember correctly, the Wiemar Republic hyper-inflated
before invading Poland in 1939 and yet as soon as war breaks out, money to support the war is nearly unlimited.
There is no more, or less reason for war today, than at any other time in human history. War in many cases is a consequence of the absence of reason.