There's a scene in The Arrival where some important muckity-muck has the following exchange with Louise (Amy Adams):
Guy: We have to consider the idea that our visitors are prodding us to fight among ourselves until only one faction prevails.
Louise: There's no evidence of that.
Guy: Sure there is. Grab a history book. The British with India, the Germans with Rwanda. They even got a name for it in Hungary.
So, what do Hungarians call that strategy?
(This exchange begins at 1:07:48.)