From the book "The Art of War" written by the great Chinese strategist Sun Tzu, some 2,500 years ago:
On Waging War
"There is no instance of a country having benefited from prolonged warfare"
On Attack By Stratagem
"There are three ways in which a ruler can bring misfortune upon his army:
(1) By commanding the army to advance or to retreat, being ignorant of the fact that it cannot obey. This is called hobbling the army.
(2) By attempting to govern an army in the same way as he administers a kingdom, being ignorant of the conditions which obtain in an army. This causes restlessness in the soldiers' minds.
(3) By employing the officers of his army without discrimination, through ignorance of the military principle of adaptation to circumstances. This shakes the confidence of the soldiers."