Where the battle against an open society gets lost:

“In a society that depends on an informed citizenry to make reasonably intelligent decisions about self-governance, (fake news) is the worst kind of trouble. And the president — who knows exactly what he is doing — is making it far, far worse. His war on the nation’s traditional press is a part of the same scheme: information warfare, meant to mess with reality and sow as much confusion as possible.”

The most effective way to make citizens subjects, divide et impera (“divide and rule”) is ancient, seeing examples before Jesus Christ. Flavius Josephus wrote in The Wars of the Jews (Book I, 167) that Syrian proconsul Aulus Gabinius, in order to suppress Jewish revolt, ultimately parted the Jewish nation into five conventions, so “the people were glad to be thus freed from monarchical government, and were governed for the future by all aristocracy.”

Niccolo Machiavelli wrote in the Sixth Book of The Art of War in the 16th Century:

“A Captain ought, among all the other actions of his, endeavor with every art to divide the forces of the enemy, either by making him suspicious of his men in whom he trusted, or by giving him cause that he has to separate his forces, and, because of this, become weaker.”

Niccolo Machiavelli
Sixth Book, The Art of War

Edward Coke, 17th Century English judge and politician, recorded in the Institutes of the Lawes of England (Ch. 1, p. 35 [original]): Eritis insuperabiles, si fueritis inseparabiles. “You would be invincible if you were inseparable.”

Photo is Edward Coke attributed to Thomas Athow, after Unknown artist, after Cornelius Johnson (Cornelius Janssen van Ceulen), via the UK’s National Portrait Gallery