"I've always wondered where explanations end and excuses begin. And is there a difference between excuses and explanations ... is an excuse a bad or self-serving explanation? I don't know. Maybe Newton's Law is an excuse for why bodies just stay at rest or in motion unless acted on by some external force. I look at the McNamara story as the-fog-of-war-ate-my-homework excuse. After all, if war is so complex, then no one is responsible."