Poverty of the State exchequer causes an army to be maintained by contributions from a distance. Contributing to maintain an army at a distance causes the people to be impoverished. On the other hand, the proximity of an army causes prices to go up; and high prices cause the people's substance to be drained away. When their substance is drained away, the peasantry will be afflicted by heavy exactions.Go here to read the introductory post to the verses of The Art of War.
~ from The Art of War, Giles translation ~