I know it's dfefinitely not true ITTL, but is it ever possible for Germany to had the ability to launch crippling non nuclear WMD strikes on the UK the way the UK to Germany with anthrax and such? Maybe if all the top Japanese unit 731 researchers somehow flee to Germany (uboat evacuation?). My gut instinct is that this is stretching plausibility to its limit at best, but it would make an interesting alternate scenario to this TL (in the Chinese sense).