The two houses are ancient enemies. The Baron has recently offered to meet with the Duke to discuss a rapprochement. The Duke fell into the trap of openly snubbing him, which then gives the Baron sufficient legal cover for his subsequent attack.
”The fool answered us, Baron!“
”Whenever did an Atreides refuse the opportunity for a gesture?“ the
Baron asked. ”Well, what does he say?“
”He’s most uncouth, Baron. Addresses you as ‘Harkonnen’ — no ‘Sire et
Cher Cousin,’ no title, nothing.“
”It’s a good name,“ the Baron growled, and his voice betrayed his
impatience. ”What does dear Leto say?“
”He says: ‘Your offer of a meeting is refused. I have ofttimes met
your treachery and this all men know.’ “
”And?“ the Baron asked.
”He says: ‘The art of kanly still has admirers in the Empire.’ He
signs it: ‘Duke Leto of Arrakis.’ “ Piter began to laugh. ”Of Arrakis!
Oh, my! This is almost too rich!“
”Be silent, Piter,“ the Baron said, and the laughter stopped as though
shut off with a switch. ”Kanly, is it?“ the Baron asked. ”Vendetta,
heh? And he uses the nice old word so rich in tradition to be sure I
know he means it.“
”You made the peace gesture,“ Piter said. ”The forms have been
obeyed.“
The Landsraad are fed a story (largely true) about this being a dispute between noble houses.
“Oh . . . ninety per cent of them are of no concern. But there are always a few . . . Houses Minor and so on, people of ambition who might try a dangerous thing. If one of them should get off Arrakis with an unpleasant story about what happened here, I’d be most displeased. Have you any idea how displeased I’d be?”
Rabban swallowed. “You must take immediate measures to hold a hostage from each House Minor,” the Baron said. “As far as anyone off Arrakis must learn, this was straightforward House-to-House battle. The Sardaukar had no part in it, you understand? The Duke was offered the usual quarter and exile, but he died in an unfortunate accident before he could accept. He was about to accept, though. That is the story. And any rumor that there were Sardaukar here, it must be laughed at.”