"We abduct my mother to save her from harm as much as for any other reason," Alia said. "We still live by the code!"
He looked down at her. She knew the dangers of inciting a mentat to compute. Didn't she realize what he had computed? Yet... he still loved her. He brushed a hand across his eyes. How youthful she looked. The Lady Jessica was correct: Alia gave the appearance of not having aged a day in their years together. She still possessed the soft features of her Bene Gesserit mother, but her eyes were Atreides - measuring, demanding, hawklike. And now something possessed of cruel calculation lurked behind those eyes.
Idaho had served House Atreides for too many years not to understand the family's strengths as well as their weaknesses. But this thing in Alia, this was new. The Atreides might play a devious game against enemies, but never against friends and allies, and not at all against Family. It was ground into the Atreides manner: support your own populace to the best of your ability; show them how much better they lived under the Atreides. Demonstrate your love for your friends by the candor of your behavior with them. What Alia asked now, though, was not Atreides. He felt this with all of his body's flesh and nerve structure. He was a unit, indivisible, feeling this alien attitude in Alia.
Abruptly his mentat sensorium clicked into full awareness and his mind leaped into the frozen trance where Time did not exist; only the computation existed. Alia would recognize what had happened to him, but that could not be helped. He gave himself up to the computation.
Computation: A reflected Lady Jessica lived out a pseudo-life in Alia's awareness. He saw this as he saw the reflected pre-ghola Duncan Idaho which remained a constant in his own awareness. Alia had this awareness by being one of the pre-born. He had it out of the Tleilaxu regeneration tanks. Yet Alia denied that reflection, risked her mother's life. Therefore Alia was not in contact with that pseudo-Jessica within. Therefore Alia was completely possessed by another pseudo-life to the exclusion of all others.
Possessed!
Alien!
Abomination!
Mentat fashion, he accepted this, turned to other facets of his problem. All of the Atreides were on this one planet. Would House Corrino risk attack from space? His mind flashed through the review of those conventions which had ended primitive forms of warfare:
One - All planets were vulnerable to attack from space; ergo: retaliation / revenge facilities were set up off-planet by every House Major. Farad'n would know that the Atreides had not omitted this elementary precaution.
Two - Force shields were a complete defense against projectiles and explosives of non-atomic type, the basic reason why hand-to-hand conflict had reentered human combat. But infantry had its limits. House Corrino might have brought their Sardaukar back to a pre-Arrakeen edge, but they still could be no match for the abandoned ferocity of Fremen.
Three - Planetary feudalism remained in constant danger from a large technical class, but the effects of the Butlerian Jihad continued as a damper on technological excesses. Ixians, Tleilaxu, and a few scattered outer planets were the only possible threat in this regard, and they were planet-vulnerable to the combined wrath of the rest of the Imperium. The Butlerian Jihad would not be undone. Mechanized warfare required a large technical class. The Atreides Imperium had channeled this force into other pursuits. No large technical class existed unwatched. And the Empire remained safely feudalist, naturally, since that was the best social form for spreading over widely dispersed wild frontiers - new planets.
Duncan felt his mentat awareness coruscate as it shot through memory data of itself, completely impervious to the passage of time. Arriving at the conviction that House Corrino would not risk an illegal atomic attack, he did this in flash-computation, the main decisional pathway, but he was perfectly aware of the elements which went into this conviction: The Imperium commanded as many nuclear and allied weapons as all the Great Houses combined. At least half the Great Houses would react without thinking if House Corrino broke the Convention. The Atreides off-planet retaliation system would be joined by overwhelming force, and no need to summon any of them. Fear would do the calling. Salusa Secundus and its allies would vanish in hot clouds. House Corrino would not risk such a holocaust. They were undoubtedly sincere in subscribing to the argument that nuclear weapons were a reserve held for one purpose: defense of humankind should a threatening "other intelligence" ever be encountered.
The computational thoughts had clean edges, sharp relief. There were no blurred between-places. Alia chose abduction and terror because she had become alien, non-Atreides. House Corrino was a threat, but not in the ways which Alia argued in Council. Alia wanted the Lady Jessica removed because that searing Bene Gesserit intelligence had seen what only now had become clear to him.
Idaho shook himself out of the mentat trance, saw Alia standing in front of him, a coldly measuring expression on her face.
"Wouldn't you rather the Lady Jessica were killed?" he asked.
The alien-flash of her joy lay exposed before his eyes for a brief instant before being covered by false outrage. "Duncan!"
Yes, this alien-Alia preferred matricide.
"You are afraid of your mother, not for her," he said.
She spoke without a change in her measuring stare. "Of course I am. She has reported about me to the Sisterhood."
"What do you mean?"
"Don't you know the greatest temptation for a Bene Gesserit?" She moved closer to him, seductive, looked upward at him through her lashes. "I thought only to keep myself strong and alert for the sake of the twins."
"You speak of temptation," he said, his voice mentat-flat.