In TL-191 Japan betrays three different allies(France, Russia and the UK) in three different cases of aggression. Each case is somehow a complete and utter shock to the former ally.
Twice Japan is permitted to keep spoils gained from either the United States or Germany despite being militarily inferior to either, let alone the two(which are allies).
I'm going out on a limb and assuming that suggesting Berlin or DC in the time frame covered in the series were not exactly known for their forgiving natures does not constitute anti-Japanese bias.