I had a young guy, he was a picture Marine. E-5, in three years and he did everything wonderful, just a superb individual. And they sent him to Vietnam, he lasted three months and I visited him in a mental ward. There is no way you're going to know. You can't stick a probe in and there's no test.
Bravery is more a matter of duty than deciding to be brave.
You decide you've got to do something because you're responsible, and not because you want to be a hero. Nelson did allow us to use his address and phone number.