Psychotechs

It is impossible to ban technology especially when technology itself must be used as the means of repression. In Poul Anderson's Psychotechnic History, the Humanists outlaw the Psychotechnic Institute and it remains outlawed even when the Humanists have been overthrown. Despite this, it is likely that both sides used psychotechnics during the conflict.

When the Solar Union fleet must assemble a sabotage team, volunteers are accepted simply because there is not enough time for the psychotechs either to pick a compatible team or to weld them "...into an unbreakable brotherhood." (Cold Victory, New York, 1982, p. 175) However, this makes the team "...an anachronism...a resurrection from old days when war was a wilder business." (p. 174)

On the other side:

"...the Humanists had had ten years in which to build a hard cadre of hard young officers to keep the men obedient." (p. 177)

It is unlikely that the Humanists' principles would make them refuse psychotechnic advice about which young officers would be most reliable. This would have been rationalized by claiming that they would dispense with the psychotechs when the war was won.

In fact, we see psychotechnics surviving into later periods and psychotechnicians coordinating Galactic Civilization in a further future.