It's no coincidence that Trump selected Ukraine as the target of his cockamamie blackmail/"investigation" scheme.

He was acting on direct orders from Putin. The goal had nothing to do with the fake investigation (though Trump might possibly have believed that). It was all about leaving Ukraine defenseless.

We would also need forms of the word for different contexts:

Addressing the leader of the movement: "Your Assholiness"
Referring to said leader: "His Assholiness"
Addressing one of the followers: "Hey Asshole!"

Referring to some of the traits that make up the movement: "Assholistic"

Behaviors of the members of the movement: "Assholery"

Insinuating somebody is on the fringe of the movement: "Assholian"

Members of the media, addicted to supporting the movement: "Assoholics"

John Berman's (CNN) label for the attack on Ottawa and various other cities around the world.

I think it's a good label.