Something everyone should study in depth is...the History of Soviet History

And by that I mean how malleable history of the Soviet Union has been

How they chop and change everything depending on the class forces at the time. And only when the world proletariat was so truly on the backfoot could bourgeois historians insist Stalin was an anti-semite with a straight face despite Stalin writing the below but they don't really care about their consistency. They just want a wall of noise of "bad stuff" coming out of the USSR so even if you're skeptical of somethings you still have the feeling that there's something "wrong" with socialist nations. It's very similar to what they did to Corbyn.

In answer to your inquiry :

National and racial chauvinism is a vestige of the misanthropic customs characteristic of the period of cannibalism. Anti-semitism, as an extreme form of racial chauvinism, is the most dangerous vestige of cannibalism.

Anti-semitism is of advantage to the exploiters as a lightning conductor that deflects the blows aimed by the working people at capitalism. Anti-semitism is dangerous for the working people as being a false path that leads them off the right road and lands them in the jungle. Hence Communists, as consistent internationalists, cannot but be irreconcilable, sworn enemies of anti-semitism.

In the U.S.S.R. anti-semitism is punishable with the utmost severity of the law as a phenomenon deeply hostile to the Soviet system. Under U.S.S.R. law active anti-semites are liable to the death penalty.

J. Stalin

January 12, 1931

https://www.marxists.org/reference/archive/stalin/works/1931/01/12.htm

Like after Sergei Kirov was killed in 1934 bourgeois historians ( and Trotsky ) told the world Stalin had Kirov killed and therefore the Moscow Trials were show trials. This is because the Moscow Trials were in response to Leonids confession (Leonid Nikolaevch - the assassin who killed Kirov) who named a group of conspirators who had been politically defeated in 1927 (and therefore had no power in the Communist Party having been outvoted on their platform by 724,000 to 4000 votes).

Bourgeois historians repeated this ad infinitum for 70 years yet since the 1990s (the collapse of the USSR) there have been 3 studies on the Kirov murder: 2 by bourgeois historians and one by Grover Furr

The 2 bourgeois historians came the conclusion Leonid was a "lone assassin" whilst Grover Furr came to the conclusion his confession was genuine and there was a bloc of Trotskyites and Zinovievites who had moved to a position of wanting to kill the Soviet leadership

Afterall Kirov wasn't the only Soviet official murdered so was Gorky, Peshkov, Kuibyshev and Menzhinsky

Anyway... One of the bourgeois historians who came to the "lone assassin" theory, Matthew Lennoe...

In the introduction to his book he spends 15 pages prostrating himself, saying how much he hates communism/socialism and stalinism. How much he hates the Soviets and is a good conservative but Stalin did not have Kirov killed.

Now why did he do this? Because he knows how ideologically charged Soviet history is and clearing Stalin of Kirovs murder opens the unfortunate pandoras box for the bourgeois that "The Moscow Trials were based on the first instance of Leonid Nikolaevchs confessions so if Stalin killed Kirov they're all obviously frame ups."

Interesting also how these studies were all done long after the general public has accepted the lie as fact (and most of them long dead given the trials were in the 30s)

I could give a million other examples: Robert Conquest once claimed that 1/3 of the working age population of the Soviet Union was in gulags for. Historians used to say that Trotsky was the real star and Stalin was a stupid mediocrity while historians like Kotkin now say " in the historical moment we're in Trotsky was nothing compared to Stalin " etc. etc.