(Spoilers for the below are for the first and subsequent books in the Dune series)
In the novel Dune and its first sequel (which is as far as I've read so far), the main objective of Paul-Muad'dib is
to prevent - or at least limit the extent of - a religious jihad, which sweeps across the universe killing countless billions in his name.
In Dune it's revealed that
Paul has a sure-fire way to permanently end all spice production, which could easily be carried out at any time. (See here for how.) In the story he uses this as a threat to the spacing guild, who can use their prescience to see that he'll go through with it if they don't cooperate.
However, my question is why he doesn't just do this anyway.
Some more details:
This would obviously be bad for Paul as a would-be emperor, since we're told his enemies have much bigger stockpiles than he does, and as a spice addict he (and most/all of the Fremen) would die without a personal supply. But on the other hand, as a way to stop the jihad it seems it should be quite effective. It would destroy the Guild and make space travel much more risky. (Without spice there is about a 1 in 10 chance of being destroyed on any interstellar journey.) This would clearly decrease the extent of the jihad, if not make it impossible in the first place. It would also destroy Shai-Hulud and the little makers, returning water to the surface of Arrakis and giving any surviving Fremen the green planet they always wanted. Even if it kills Paul that doesn't really matter, because he considers actions that would result in his death several times and only chooses not to do them because it would make him a martyr.
Of course, an obvious answer is
"Paul's prescience allows him to see the long-term consequences of that action, and they must be bad or he would have done it."
But I'm wondering if it's discussed more specifically than that.