Dune is a story about power.
Paul finds himself in the position to decide whether or not he wants to seize power. Just as these characters found themselves in the same position…
Gandalf and Galadriel were both tempted with power. They both saw a vision of a future where they had the power to choose what the world would be, the power to force the world to their will. The moral virtue of both characters is the fact that they both said no.
Paul finds himself raiding in the North with pressure mounting for him to go South and seize power, launching a Jihad across the universe with nearly a hundred billion dead. Is this the only way forward? No. But he knows it’s what will happen if he takes power and makes the decisions he ends up making.
But he does it anyway.
In my opinion this speech is one of the best scenes in film. Paul radicalizes a room full of skeptics and launches his Jihad.
Paul believes he is choosing the lesser of two evils by launching the Jihad. He believes that committing 60 billion deaths is the lesser evil. To what? We don’t really know, but he assures us it would be worse.
This is a story about a psychopath and the post-hoc justifications he uses to gaslight the universe into thinking his evil deeds are actually good.
Eventually he comes around to this perspective of himself.