Art of Oil War

Listen up, buttercup. This joke implies that countries might invade other countries for their oil, and then try to justify it by saying it's not a war crime. It's like saying stealing candy isn't wrong if you really, really like candy. Sun Tzu wrote "The Art of War" which is ironic because this "rule" would actually cause more war. And I bet you don't even know who Sun Tzu is, huh?