>>it needs that fuel to feed it's army<<
He He, that conjures up images of loads of men eaten petroleum sandwiches.
About war and economy. It's great if like the more recent wars you are the one bombing someone else's country with no fear of being hit yourself. But in big wars like WW2 where the winners also take a good hammering then no it's not good for the economy. Your infrastructure and production facilities get destroyed and a portion of your working population get killed. Hence why for many years after WW2, we still had rationing and stuff till we could rebuild our country's ability to produce.