Probably a variant spelling of "paeanistic".
paean also pean n.
- A song of joyful praise or exultation.
- A fervent expression of joy or praise.
- An ancient Greek hymn of thanksgiving or invocation, especially to Apollo.
Found also here:
The song or shout of praise, of battle, or of triumph.
Another possibility is reference to the surname "Paen".
Paenism refers to the policies and governmental philosophy of Generalissimo Timothy Paen, current Premier of the Stratocratic Republic of Ikeria.
Paenism, when used in its broadest sense, refers to stratocratic states comparable to the SRI , i.e. that are characterized by an overly centralized state, totalitarian figure head, secret police, propaganda, and especially brutal tactics of political coercion.