I think Alibaba knows this already though. When he asked for the Airships, Sinbad quoted him again about how Alibaba said the Kou should be saved by their own strength. From a business standpoint, it make sense what Sinbad did, but from a moral standpoint it is Sinbad fault that the Kou Empire...
In a way, Sinbad is sort of doing the same thing as the Kou Empire once did. Maybe not as extreme as Kou, but still... somewhere in Sinbad's plan is downfall. Being connected to David is still bad thing. Alibaba has said he didn't feel like Sinbad was the same person. If he is changing, it...