“Stalin is one of the most extraordinary figures in world history. He began as a small clerk, and he has never stopped being a clerk. Stalin owes nothing to rhetoric. He governs from his office, thanks to a bureaucracy that obeys his every nod and gesture. It's striking that Russian propaganda, in the criticisms it makes of us, always holds itself within certain limits. Stalin, that cunning Caucasian, is apparently quite ready to abandon European Russia, if he thinks that a failure to solve her problems would cause him to lose everything. Let nobody think Stalin might reconquer Europe from the Urals! It is as if I were installed in Slovakia, and could set out from there to reconquer the Reich. This is the catastrophe that will cause the loss of the Soviet Empire.”

In an interview to Независимая Газета http://www.peoples.ru/art/literature/prose/roman/alexander_zinoviev/

Source: Inside the Third Reich: Memoirs (1970), p. 306

Letter to John Middleton Murry (5 August 1944), published in The Collected Essays, Journalism, & Letters, George Orwell: As I Please, 1943-1945 (2000), edited by Sonia Orwell and Ian Angus
Context: Of course, fanatical Communists and Russophiles generally can be respected, even if they are mistaken. But for people like ourselves, who suspect that something has gone very wrong with the Soviet Union, I consider that willingness to criticize Russia and Stalin is the test of intellectual honesty. It is the only thing that from a literary intellectual's point of view is really dangerous.

Speech at the Baquedano Theater, Santiago, Chile (1953) https://web.archive.org/web/20101222183523/https://www.northstarcompass.org/nsc1011/nsc1011.pdf

Reported by law librarian Ed Bander, in "Doing Justice", 72 Law Libr. J. 150 (1979), as having been heard at a speech given at New York University.
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The Tragedy of Spain (1937)
Context: For two decades the supporters of Bolshevism have been hammering it into the masses that dictatorship is a vital necessity for the defense of the so-called proletarian interests against the assaults of counter-revolution and for paving the way for Socialism. They have not advanced the cause of Socialism by this propaganda, but have merely smoothed the way for Fascism in Italy, Germany and Austria by causing millions of people to forget that dictatorship, the most extreme form of tyranny, can never lead to social liberation. In Russia, the so-called dictatorship of the proletariat has not led to Socialism, but to the domination of a new bureaucracy over the proletariat and the whole people. …
What the Russian autocrats and their supporters fear most is that the success of libertarian Socialism in Spain might prove to their blind followers that the much vaunted "necessity of dictatorship" is nothing but one vast fraud which in Russia has led to the despotism of Stalin and is to serve today in Spain to help the counter-revolution to a victory over the revolution of the workers and the peasants.

Opinion: No, Bashar Al-Assad is no Joseph Stalin http://english.aawsat.com/2015/10/article55345413/opinion-no-bashar-al-assad-is-no-joseph-stalin, Ashraq Al-Awsat (16 Oct, 2015).

Speeches, Moscow Address

Source: "Let the Record Speak" 1939, “The Truth about Communism” https://babel.hathitrust.org/cgi/pt?id=mdp.39015051180423&view=1up&seq=5 (1948), p.12