The Germans have a long history of not liking America very much.
The Germans seem to have gone from proclaiming themselves the master race to pretending to be the master moralists.
Germany is certainly our ally. But they continually make it hard to
think well of them--and I'm not even harboring grudges over two world
wars.
UPDATE: Related thoughts.
As I've asked before, why do Europeans who resisted attempts by the Kaiser, the Nazis, and the communists to rule them so eager to be absorbed by the proto-imperial European Union that Germany dominates?
The Germans have been our allies, but perhaps that is because a strong US-dominated NATO gives them no choice.