He literally wrote a book about it. Lebensraum in the east was a core ideological principal of the Nazi party from the very beginning. A huge part of his idea of the supremacy of the German race" was the rugged individualism, salt of the earth farmers that would tame the "uncivilized" reaches of eastern Europe. The whole military buildup during the 1930's was with one goal in mind, the eventual conquest of territories at the expense of the USSR

There is plenty of evidence of how advanced the Japanese program was, the answer is, not very. What you're assuming is that there is all this other non-existent evidence to indicate others. This isn't "what aboutism" you've applied a logical framework to the Japanese program that is equally applicable to ghosts, Bigfoot, alien autopsies and the like. We have evidence that the Japanese program never produced fissile material, I'm not sure what kind of "evidence" you would accept to prove that they didn't, just like Nazi Germany didn't build a base on the far side of the moon (OMG what if they DID, and all the evidence was destroyed!!!!)

Hitler's whole raison d'etre was to obtain living space for Germany at the cost of the Soviet Union. The problem is that by layering all these changes to aims, goals, perspectives and philosophies, there is a good chance you don't end up with WWII at all

Extra ordinary claims require extra ordinary evidence and Occam's razor holds more often than not. An industrial effort sufficient to produce sufficient fissile material in sufficient quantity to build a bomb is MASSIVE. If there were some effort "to destroy all of the data", there would be evidence of that effort. There isn't. Conventional bombing raids can damage industrial facilities, but they can't wipe them off the face of the Earth. Had there been some super secret industrial effort in North Korea to build a nuclear weapon, the Soviets would have grabbed anything they could. We can look at historical records and see how they grabbed assets in Germany, how they grabbed other assets in Manchuria, the spies they had in the Manhattan project, but Japanese nuclear weapons.... crickets. Again, your logic means we should put credence into alien autopsies, the Loch Ness Monster and Big Foot. After all we have "low quality eye witness accounts"

That's not how the study of history works. History is based on primary evidence. There is zero reliable testimony from anyone that Japan was anywhere near close to producing fissile material at the purity or quantity needed to build a bomb. At this point you're in the same league as alien autopsies, the Lock Ness Monster and Bigfoot Like I said, the first part of Wilcox's book does a good job describing the work that Japan did around nuclear weapons (very small scale, limited to fundamental research, and extremely strapped for resources), close (but not quite) to where the allies were in 1940. Then it goes off into wahoo land about secret facilities that no one knew about, that were conveniently all destroyed, leading to a nuclear test that no one ever detected, nor found any evidence of.

At a certain point you end up with, "if the Nazi's weren't the Nazi's, Germany could have won WWII". While breeding of Plutonium does occur in commercial reactors to some degree, much of it is burned up by the reactor as it operates, you also end up with a variety of Plutonium isotopes which make it almost impossible to construct a bomb. Pu-239 is what you want, but reactors also produce Pu-241 and Pu-242 which are intense neutron emitters that cause pre-detonation. Reactors designed for Plutonium production allow samples of U-238 to be placed in the reactor for short periods of time so that Pu-239 and be bred, and then removed before too much Pu-241 or Pu-242 builds up (however even in these cases, there is still enough pu-241 to cause challenges). The vast majority of commercial reactor designs can't do this. The other big challenge is the scale of industrial facilities needed to produce fissile material at scale. Sure, Germany built the Mittelwurk to produce V-2s in a secure manner, but this was nothing compared to the size of places like Hanford or Oak Ridge. Either Germany would need years to build massive underground facilities for them, or they'd be built in the open, and bombed flat the moment the Allies found them .

Germany never enriched any Uranium (even the Japanese did some preliminary work around Thermal diffusion), nor did they ever get close to building a reactor capable of breeding Plutonium. So to say that they "didn't get close to producing any fissile material" is entirely accurate. Nazi Germany went with heavy water due to a combination of mathematical errors and boron contamination in the coal produced graphite they had access to. They ruled out graphite as a moderator in favor of heavy water (which is far more difficult to work with). While it's entirely possible that they could have built an atomic pile similar to what Fermi did in Chicago, The largePlutonium breeding reactors like the ones built at Hanford weren't even on Germany's radar. Heisenberg also miscalculated the critical mass of Uranium which led them to believe the concept of a bomb was impractical, after that, most of the work was around conceptual naval reactor designs. While the critical mass of Plutonium Pu-239 is smaller than Uranium U-235, it is much harder to use in a bomb because of Pu-241 contamination. You need a complex implosion design as the critical mass needs to be assembled faster to prevent pre-detonation (fizzle). There little evidence that Germany seriously considered the use of Plutonium for anything, never mind a bomb.

The Sanger anti-podal bomber was more a paper napkin exercise than reality. When the USAF started studying it in depth there were a lot of massive gaps in knowledge that would have prevented it from going forward in any shape similar to the concept

No, they never got anywhere close to producing any fissile material (either U-235 or Pu-239), never mind enough to build a bomb

It was only months because the US paused fissile material production when Japan surrendered in order to reconfigure a number of facilities at Hanford and Oak Ridge. Had the war continued the US would have been producing 1-2 bombs per month, ramping up to 3-4 a month by end of 1945

The Gloster Meteor flew a full year before the Me262 and entered service at almost the exact same time

With the Japanese surrender, there was a pause in production of fissile material as there were several opportunities to optimize the use of Hanford reactors, the gas diffusion facilities at Oak Ridge and improved bomb designs. Had the war continued, the US was capable of producing 1-2 bombs per month, rising to 3-4 by December 1945

The old, if Hilter wasn't Hilter, Germany could have won WW2

Little Boy weighed 3 times the maximum bomb load of the AR234 and 5 times that of the V-1

Yes, Japan had an incredibly small and underfunded nuclear program, that barely started some research into thermal diffusion as a potential way of enriching Uranium. A method that gets you from about 0.7% to 1.1% (no where near the 70%-80%+ you need to build a bomb). The first half of Wilcox book does a good job of summarizing the work that was done, then it veers off into purely fictional wahoo territory that bears zero resemblance to reality. Imperial Japan was in no, way, shape, or form, anywhere remotely close to developing at nuclear weapon