Here's an interesting read.

The story of Hieronymos From this I realized one of the secrets of the rise of the Roman Empire is that they issued a specific currency for the war. This is what the Allies did. And this is what the Americans are doing. Well not specifically; symbolically, but it gives rises to the concept of war and raising money. After all Income Tax was put forth as a war payback/payment measure. What's the real cost of war? Well someone at some point has too assign a value to that. Is it the same for all of us? What a radical concept that would be. Or is it so radical?