User blog comment:Mythical zoan fruit enthusiast/I'll never forgive you!!! Unless.../@comment-4904935-20130810180142

Well it's because of BB the WG was able to get their hands on Ace and he ended up on the execution platform! As a marine, Sakazuki was just doing his job. Luffy wouldn't necessarily forgive Sakazuki but if he was given a choice to take out either of them, Luffy would go after BB first.