As far as I can tell, Nashimoto iOTL was arrested as a war criminal, but it seems he was more or less a hostage for the behavior for the rest of the Royal Family rather than someone that *anyone* in the US Military administration wanted put up against the wall and shot.
MacArthur being viewed as unable to understand Go.
The question is whether Terauchi is doing this entirely selflessly or whether he will expect the two men to owe him loyalty. (The third option is that he is doing this not selflessly, but because he is taking a gamble politically that has turned out *really* well)
Good for Nagano. Almost certainly will live longer iTTL.
Also, looking up Nagano, I ended up at the Wikipedia page for Sugamo prison. This lead to the page on the "Peace Preservation Law". I'm not really *that* sure the Law would be that much less Draconian than iOTL, the Japanese-Soviet relationship still isn't going to be great. Which leads to another topic. Whither Richard Sorge?
I wonder how much time it would take to just set up a game of Ultimate Shogi! Interestingly enough, the huge variants are very hard to play strategically as they require the player's attention in so many places- it can become a game of tactics and operations.
Prince Nashimoto always stuck me as the wrong scapegoat, as he was essentially pushed out of any sort of military planning precisely because he was not a radical militarist. If any member of the Imperial Family should have stood to account, it should have been Prince Yasuhiko Asaka.
Nagano will indeed live longer- thus far, the war has been less stressful for him. The IJN has been successful in virtually everything they have attempted. Together with Navy Minister Mitsumasa Yonai, the Navy has also been able to get nearly all of its projects funded, so that the Communazis don't come and bomb Tokyo next week.
For Field Marshal Count Terauchi, the answer is all three. He is the son of a former prime minister and knows how to play politics as well. Such acts are also part of
Bushido- the commander is expected to show generosity and duty of care; the subordinate returns it with absolute loyalty.
As for Sorge, I could see him posing as a
Svobodnik in Manchuokuo, trying to feel out what plans Japan has against the Soviet Union.
Considering close ties between Japan and Britain, Japan's cryptography is probably more advanced than OTL. Especially since IIRC, plenty of educated Jewish refugees fleeing Europe to the Far East don't really mind helping serving in Japan, as mentioned by
@WaterproofPotatoes at one point. Particularly in the cipher department. Considering how Russian antisemitism was a thing of legend long before the Nazis turned up, I'd say they'd be quite happy to make sure the Soviets aren't reading Japan's diplomatic and military codes.
If anything, it'd be the other way around. That is, the Japanese are routinely intercepting and reading Soviet diplomatic and military traffic, with intelligence sharing and cooperation with their allies in the Commonwealth.
That is exactly the case!
OTL, there was a widely-believed idea that if Japan helped the Jews, they would return the favour by aiding Japan and the Empire by helping to generate wealth- a negative stereotype spun into a superpower!
TTL, Japan does have much better military intelligence, taught by British and Polish spymasters. Japan eagerly cooperates with the British and Polish governments to find out as much as possible about the USSR, and in turn, provides aid to the Polish government in exile. Evenfar- rightist Poles tend to view Japan favourably, as Japan will welcome the Jews they don't want.
There is extensive spying on the Soviet Union, and a focus on finding out how Mao is being funded and acquiring weapons- the IJA, Manchukuo Imperial Army and the Mengjiang National Army have all devoted time and resources to fighting the Communists. The Chinese Nationalists have dispatched Du Yuesheng to deal with the Communists, by everything from counterinsurgency warfare, to dropping opium on Communist villages and encampments to try to make them into addicts.
There are indeed many Jews serving the Empire of Japan, and Manchukuo in particular. Manchukuo has no quotas on Jewish immigration, and laws in place preventing discrimination against Jews, permitting the free exercise of Judaism, and even penalizing the sale of food falsely labeled as Kosher- and
Svobodniki (Free People; anti-Communist Russian emigres) are reminded that they have the same protections for the Russian language and the Orthodox Church, so they must not do anything that would upset the balance in Manchukuo. The cipher department is well-represented, as the ability to speak German or Russian is in high demand.