It probally would have happened around the same time during the 1950s.
Nukes needed a real enemy to push their creation, the Japanese went crazy but that was a multiple nation dog pile. Between China, the brits and the american's the japanese were going down and every one knew it...
except the nuts in charge.
No it takes a real threat to get that kind of money spent, When Stalin died and he was replaced by that Psycho.... Well thats what prompted the creation of the bomb in the empire, In france and In america and even then it took more then 30 of the damned things before the soviets gave up.
Honestly I don't see nukes being made before 53 at the very least.
I'd agree with that. However if Germany hadn't had its flirt with Fascism more resources might have been available in Britain for its own Nuclear program. Japan was always going to become expansionist so even with a stable Germany the need will be there.
Perhaps the British would have finished their Nuclear Device first instead of the Americans? Either way, I do think someone was going to drop a Nuke on Japan. The attempted invasion was a failure from its inception.
You'd need some major butterflies to make the invasion a success, and without it Nukes are the only option for ending the Wars.
I've heard the Rhineland-War, the Anglo/America-Japanese War (aka the Pacific War to us Americans), and the final bloodbath of the Third Balkan War in the late 40's as grouped together as "The Second World Wars", but certainly not the Rhineland War alone.
We call it the Anglo-Japanese War here in the UK

When you guys finally got yourselves in gear (the USA, late for every war!), we'd already signed the 2 year ceasefire. When it picked up again we also refer to round 2 as the Pacific War or the Anglo/America-Japanese War.
Yeah, once the Soviets started getting aggressive rearming the Chinese Communists (the death of their Mao in the war against the Japanese really set them back) the Allies switched from occupation to reconstruction pretty damn fast.
Can you imagine what the NSDAP would have done if they had managed to get a hold of Germany farther down the line, once they'd pulled off the Wirtschaftswunder? Five years and change running a shaky pseudo-democracy and they managed to convince everyone that picking a fight with France, the goddamn strongest military power on the continent (at the time), was a good idea.
The thing is I think Mao might have been more resistant to Soviet pressures. He was more interested in turning China into a power in its own right. Had he lived China may not have tacked so close to the Soviet line.
And I ignore all of those nutters who think the Fascists could have pulled a comeback. The Germans, like the British, are not natural Fascists. The Beer Hall Putsch only succeeded due to force of arms, it was never popular with the majority of people.
There is a reason no Fascist party has ever been elected democratically. People aren't stupid. Even Italy turned against Mussolini when he started his 'New Rome' madness.