Rosh continues his power over others and his thievery through fostering the notion that he is working towards the cause of Israeli freedom from the Romans. Daniel, like others, believes that Rosh is going to raise an army and rout Rome from Israel, allowing the Jewish monarchy to rise again. However, Daniel realizes that Rosh is only after personal profit, and doesn't care about the cause except as a tool to promote himself and gain followers.
"The things we've been doing for Rosh weren't what we planned when we started the band. Attacking people on the road, especially our own people, isn't going to bring the day any closer. We haven't weakened Rome at all. We've only weakened ourselves instead."
(Speare, The Bronze Bow, Google Books)
After Daniel breaks with Rosh, he does not appear in the story again; the villagers are already dissatisfied with Rosh because he is preying on their caravans and cattle, not attacking the Roman forces. Rosh cannot actually fight Rome; it can safely be assumed that Rosh will continue his thievery until someone catches and kills him. Rosh does not "win" in any meaningful way, not in his stated cause and not in the hearts and minds of the people. Instead, he becomes an enemy, and is vilified and rejected.