WWYD: What would you do?

In Amir's situation back when he saw what happened to Hassan, what would you do?  Amir was obviously too afraid to say anything or do anything, I mean it's a scary situation for him to be in, and as a young boy I wouldn't expect he'd know what to do.  There's always different ways to look at something, no matter what it is.  I believe in that situation, personally I would definitely tell someone.  I would feel shame about not helping Hassan, but in all honesty, if Amir were to step in, Amir probably would have been raped too.  It's a choice he had to make in a split second, unfortunately his decision haunted him for years and years...