What would happen if a Culture ship turned up in orbit around Arrakis?

The Mentats would be up in arms, of course, at the presence of an AI. The Bene Gesserit would try to control the Culture, and be overwhelmed. The Navigator’s Guild would strike at the prospect of ships that didn’t need them. The Empire would convulse in a jihad it could not win, against a target that didn’t care much what it did.

The Culture would be unaffected. Spice would become a fashionable drug for a while on some ships, then fall out of vogue. Even true foretelling becomes uninteresting with no disasters to avert.

Thus:

While questing through the timelines undefined
They say the Muad’Dib beheld a ship
No navigator steered while in the grip
Of worm-bred spice. The pilot was a Mind
Constructed like a man’s, but smarter still.
Its crew were men, but fattened with excess.
A culture without want, without distress
To test a man, to strengthen mind and will.
The Kwisatz Haderach then closed his hand.
For he who sees all roads can pick his way:
Which branchings to ignore, which let to stay.
This path he blocked, as if with drifting sand.
A lucky man, who may his jihad choose
Forknowing which he would most surely lose.

Originally posted on Making Light