Originally Posted by I Am The Knight
And so you're OK with "I won't kill you, but I will let you die a horrible death by train crash" instead of straight up killing then, yes?
I believe that moment was acceptable because Ra's had put himself in that position. He tells Batman before boarding the monorail that his fate would "lie with Gotham", meaning he was on a suicide mission. By the time Batman had subdued him the train couldn't have been stopped and there wasn't really a way for Batman to save Ghul and himself. The dialogue was iffy, but the circumstances were appropriate IMO.