As much as I think Einstein's work helps he is not critical to get anyone an atomic bomb, if anything I think he continues to work on the theoretical side and publishes enough to help the other scientists working in applying this stuff. Without a war I think that science is more open and continues to be German dominated, a lot of the underlying science will be in German papers, patents and lectures. And without the war I do not see any greater fear of German militarism than the military of any other country, the Kaiser is a bit loose on deck at times but overall his government is a democracy and outwardly not less peaceful, in fact I would argue that few would fear giving this science to any industry or military as our capacity for self destruction has not yet been proven. That said I could argue that both France and Britain have the know how and the resources, the USA should be far more distant actually, it has a less robust linkage between science and industry, corporate or government money and university, that is a product of WWII. Oddly I see the science being published openly right up to the moment it gets very real, that likely levels the playing field in many ways. Without the horror of poison gases and terror bombing the atomic bomb either does not look worth while or looks like just a bigger sort of boom. You pick, implications cut both ways. But if I need to lay down money on a bet I think Germany has all the ingredients to build one first.