“War is Peace” is doublespeak; an inherent contradiction. Anybody can say it and still see the contradiction and believe that it isn’t true. Doublethink is the internalization of that doublespeak. A Party member says it and sees no contradiction. Deep in their hearts, they understand that to be in a never ending war is to experience neverending peace.

All that to say that doublespeak was certainly a thing in the novel, as it labours on the distinction between doublespeak and doublethink.

Maybe OP didn’t just read it then. Maybe, like me, they read it years ago and misremembered