I have some difficulty seeing the Palestinians being all lovey-dovey with the Jews under the presented scenario (ie., I don't see how it would keep the OTL severe Antisemitism of the Palestinians in check).
It's certainly an overly optimistic guess, in hindsight, on my part. We'll have to see how the apparent creation of a 'pan-Semitic' ideology works out. Still, I think that anyone who wants to try something funny to the opposing party is going to run into a lot of problems. After all, both just got done fighting a war side by side - grudging as an alliance might've been - to fight for their independence. While there will almost certainly be power plays to try and hand wave the influence of one another, I'm not sure how much good it'll do either of them.
Or, worst case scenario, we get almost as many problems as OTL, and the USSR and UASR have to keep a close eye on Palestine. Perhaps a comparison with OTL's USA-Israel relationship, except in this scenario, it's much more of a "Play nice with each other or we'll gut our trade with you," or something like that.
Also, I don't know how many Jews would want to flee to the
USSR
I'd forgotten about the Doctors' Plot, actually, so this is well met.
However, while anti-Semitism in the USSR surely isn't going to die with him, if Stalin dies during WWII ITTL (which, if I'm not mistaken, Jello hinted at) then that would be butterflied away. It's going to suck for a long time being a Jew in the USSR, but my assumption for those Jews after the war in places like France or the U.K. might not care if it actually is better, so much as the perception is that it would be than their former homelands, if that makes sense.
Still, the UASR having an even larger Jewish population than OTL's USA strikes me as the likely outcome here.
I imagine that they would agree it's a strategically important area which is incredibly ripe for revolution. I doubt they would agree on much besides that, though! I can see separate Marxist-DeLeonist (or whatever, UASR-aligned I mean) and Marxist-Leninist (USSR-aligned) rebel groups, each receiving backing from their peculiar sponsor. (Rather like OTL in many countries, actually...)
Oh, for sure. Like I said: they'll agree that the French and Brits have to go, along with all this 'apartheid' nonsense that the Afrikaner are eager to put in place. How they're going to go about doing that, of course, is an entirely different story. South Africa is such a tantalizing prize because it's one of the only 'White Dominions' where revolution looks like a real possibility.
Problem for the Comintern is that the FBU totally knows this too. They're going to have to play really nice with the black population they're sitting on if they want to avoid. Of course, then you've got your Afrikaner administrators and politicians who aren't going to like that one bit...
During WWII I'd expect a gentlemen's agreement of sorts shaping up between the Americans and Soviets over the Korean peninsula, making it a neutral Red state as a buffer between their respective spheres of influence.
I believe it was teased in
A Red Dawn that in the future, Korea will be a neutral socialist country, like you said. Basically it exists so that the USSR and UASR don't have to fight over who gets a sphere of influence there. As long as the boys in Seoul keep their heads down, they should be fine...for the most part.
How will China turn out? JB previously hinted that Mao won't end up in charge, due to the Chinese Civil War not picking up again after WWII.
Similar to the above, if I'm not mistaken and unless plans have changed, China's going to be in a situation where they're not Communist, but are a socialist republic (ala Korea, I'd think). China will apparently look toward the Soviets diplomatically much more than the Americans. This makes sense, in hindsight, why Japan is a closely allied Communist state with the UASR. What'll really be fascinating to see is what happens to China when the Americans and Soviets stop being antagonistic to each other around 1980 or whenever it is they decide to work in lockstep again.
In that case, do expect yet another futile war in Indochina...
Jello's gone on record, I believe, for being a fan of Kim Newman's
Back in the USSA, one of whose short stories features John Rambo training guerrillas in an alt-Vietnam War. Building off of that, pretty sure that Vietnam was mentioned as another state within the UASR's sphere of influence.