He had many dinners alone with General George Marshall during the war, after “two stiff, bourbon old-fashioneds which the Chief liked to mix himself. There would be talk of course, but absolutely no war talk. That day he probably had had to make decisions that affected the fate of nations; tomorrow he would face problems equally crucial. But that evening he would be calm and unworried as he listened to my chatting. Once, I asked him how he stood up under the strain; he answered: ‘I’ve had to train myself never to worry about a decision once it’s made. You worry before you make it, but not after. You make the best judgement you can about a problem – then forget it. If you don’t, your mind is not fit to make the next decision.’”
Frank Capra The Name Above the Title