Let's make it more into a hamfisted analogy for the modern day.
Say the U.S. is pulling out in great numbers, and terrible attacks still occur, but the new German provisional government is slowly getting its act together, and the previous internecine warfare between the Nazi Werwolf insurgents and Bavarian Catholic militia dies down thanks to the "Awakening Movement" led by a coalition of Prussian Junker families. In fact, the Werwolf groups are quickly getting eliminated, but there is nervousness that Austria is regaining undue influence in Germany, as a neo-Dollfuß Austrofascist government is in formation there. Unfortunately, the U.S. troops have no choice but to pull out and redeploy its troops to Japan, to complete the war it had started earlier there, where Imperialist fighters continue to hide in the mountains...
I'm making this up as I go along because I haven't actually read the book.
Oh, COME ON