Its used as a mask so that others wil think that somehow theft, murder, biggotry and the extintion of other races are somehow noble acts when done in the name of a god or an ideal.
In theory, that's a noble enough act of de-mystification, but Alex Von Tunzelmann's script is premised on the idea that Churchill's piss - poor sense of military strategy and the disaster of the World War I Gallipoli campaign were somehow proof of his greatness.