How and why does Max imagine and reinvent the Fuhrer in his dreams? (Part 5)

Max is imagining and using his situation to stay strong.... to stay motivated, all while illustrating his knowledge that the danger is real. He fantasizes about fighting Adolf Hitler in a boxing ring. The crowd -- millions of Germans -- cheers for Hitler and abuses Max, who arrives alone. Even the referee is biased towards Hitler. There is only one round, and Hitler punches Max for hours. Max falls, but slowly rises before the count, then at last aims a series of blows at Hitler's mustache. Hitler falls, then returns to his feet, removes his gloves, and addresses the crowd. Hitler delivers a speech threatening that Max is plotting against them, trying to enslave them. He asks them to come into the ring to "defeat this enemy together," and they do. In the end, a girl comes in with a newspaper and tells Max that the crossword is empty, then the fantasy is over. A few nights later Max tells Liesel about his recurring dream of fighting Hitler and that he is training for it.