I totally understand where you're coming from. I also agree with everyone else about hitting dogs- it's never appropriate. But last week my 4 month old puppy (big puppy) killed one of my bantams. I got mad and smacked him on the nose. It was wrong and I know that, and I won't do it again, but it's hard to think rationally when you're that mad. Especially because once I calmed down I realized it was 100% my fault- he's a puppy, and I shouldn't have let him out of my sight, but he had been so good with the chickens so far that I got overly confident. I know everyone says once they've tasted chicken it's over, you can't train them NOT to kill them, but I refuse to believe it. I mean, in my case he's still a puppy, and he knows his place in our pack (the dominance thing above, btw, is really good advice- dogs who respect you like a pack leader are much more likely to listen... I know people think Cesar is "mean" or whatever, but his methods make the most sense to me because he treats dogs like dogs, not people, and communicates with them in ways that make sense to dogs, which is why they are so effective so fast... anyway, I digress...), and it only happened because I couldn't see him (and he couldn't see me) and he's still learning. I feel that I can counteract whatever positive reinforcement he got from killing the chicken by maintaining our pack order and showing him that the chickens are mine and he isn't to touch them.
And, of course, I won't be letting him around them unattended until he is 3, which is when a dog is considered an adult (0-1 is puppy, 1-3 is like the teenager phase), and then only if he proves himself worthy of my trust. I won't chain him- he ignores them when he's with me, and I'll just make sure either he comes inside with me any time the chickens are free ranging.
No, I have no advice to give- at his age I wouldn't be as faithful that this event could be overcome. I just wanted to say I understand what you're going through!