Mark - I cannot resist a Phillip K. Dick style contrafactual. Here’s my question: If the old lady (or Time Lord in Drag) should focus on killing Stalin and Beria (and why not Lenin? He was still around), would we have to worry about Hitler at all? I mean does Hitler rise to power without Stalin?
Of course, the T-LiD (again: Time Lord in Drag) may have in fact killed someone he/she believed to be far worse which in turn resulted in the space-time blowback of Hitler and Stalin. You never know.