The use and corruption of language by power structures as a form of mind control is a very important theme in his work. The only logic to them is that they are supposed to destroy the meaning of words, and break down the positive or negative associations people have with those words. They aren't supposed to make sense, and that's precisely the point.
War elicits great patriotism and devotion to country; it also promotes sacrifice and giving to the community over oneself.
So, if there is constant war, the people are constantly giving, sacrificing, and pledging devotion to their government. The people probably believe that to mean that having total freedom is actually a way to become enslaved to your senses, weaknesses and vices.
By invoking a paradox, you destroy meaning and control thought.
You can see exactly this happening in the modern world. Freedom fighters are terrorists if they're foriegn, but "disturbed" if they're domestic.