Who said this?
A speedy victory is the main object in war. If this is long in coming, weapons are blunted and morale depressed. …
When the army engages in protracted campaigns, the resources of the state will fall short.
When your weapons are dulled and ardor dampened, your strength exhausted and treasure spent, neighboring rulers will take advantage of your crisis to act. In that case, no man, however wise, will be able to avert the disastrous consequences that ensue.
Thus, while we have heard of stupid haste in war, we have not yet seen a clever operation that was prolonged. for there has never been a protracted war which benefited a country.
Therefore, those unable to understand the dangers inherent in employing troops are equally unable to understand the advantageous ways of doing so.
Those adept in waging war do not require a second levy of conscripts nor more than one provisioning. They carry military equipment from the homeland, but rely on the enemy for provisions. Thus, the army is plentifully provided with food.
When a country is impoverished by military operations, it is due to distant transportation; carrying supplies for great distances renders the people destitute. Where troops are gathered, prices go up. When prices rise, the wealth of the people is drained away. When wealth is drained away, the people will be afflicted with urgent and heavy exactions. With this loss of wealth and exhaustion of strength, the households in the country will be extremely poor and seven-tenths of their wealth dissipated. As to government expenditures, those due to broken-down chariots, worn-out horses, armor and helmets, bows and arrows, spears and shields, protective mantlets, draft oxen, and wagons will amount to 60 percent of the total.
Hence, a wise general sees to it that his troops feed on the enemy, for one bushel of the enemy’s provisions is equivalent to twenty of one’s own and one shi of the enemy’s fodder to twenty shi of one’s own.
[. . .]
Hence, what is valued in war is victory, not prolonged operations. And the general who understands how to employ troops is the minister of the people’s fate and arbiter of the nation’s destiny.