According to Wikipedia, as of 2010 the US military has 52,440 people in Germany, and as of 2013 the German military had 188,921 active personnel and as of 2010 144,000 in their reserves.

That falls a bit short of "occupation" in my book. There has in fact been at least one technothriller based on the US military fighting its way out of Germany, based of course on the Anabasis (http://en.wikipedia.org/wiki/Anabasis_(Xenophon) Xenophon and 10,000 Greeks fighting their way out of the Persian Empire).