Straight Left followed this method and also claimed to be simply a left-wing weekly aimed at the wider Labour movement. It managed to dress this up by recruiting a few far-left Labour MPs — none of them known for their forthright criticism of the Soviet Union, all now dead — such as Joan Maynard (popularly known as “Stalin’s Granny”) and James Lamond, founder chairman of the British-East German Society, to serve on its editorial board.

Milne served as Straight Left’s business manager. There is no evidence that he himself ever joined the Communist Party. Indeed, it would have served the interests of the faction better if he was not a formal member.

Straight Left was an incredibly dull read, perhaps intentionally in order not to reveal its true purpose. The paper combined calls for immediate mass nationalisation and other left-wing Labour demands with slavish, drooling support for the Soviet Union. Its back page contained a regular column, written by Nicholson, under the byline Harry Steel. The pseudonym was designed to honour Harry Pollitt, the Stalin-era general secretary of the Communist Party on the one hand, and Stalin, the “man of steel” himself, on the other.

Whatever Seumas Milne may now claim, Straight Left was simply a hard-line anti-reformist pro-Soviet faction within the Communist Party — and Milne was at the heart of it. Twenty years ago, when I interviewed Nina Temple, the last general secretary of the Communist Party of Great Britain (it was dissolved in 1991), for a university dissertation, she described Straight Left as the most slavish defenders of the unreformed Soviet Union she had come across in her entire lifetime in the party. In the words of Jack Conrad, Straight Left may have “fooled some numbskulls into thinking that it was just a left Labour paper”.

Has Milne moved on from his youthful dalliances with Stalinism? His Guardian columns suggest otherwise. He has written that “the number of victims of Stalin’s terror has been progressively inflated over recent years” and that “Communism in the Soviet Union, eastern Europe and elsewhere delivered rapid industrialisation, mass education, job security and huge advances in social and gender equality”.

Milne sees himself as a representative of the anti-imperialist Left — but it is a special interpretation of imperialism, namely that formulated by Lenin in his 1916 pamphlet Imperialism: The Highest stage of Capitalism. In a 2011 speech, Milne declared: “Under modern capitalism, imperialism in essence is the use of force and coercion in all its forms . . . to extort profits above what can be obtained through ordinary commercial exchange.” Imperialism is not Russia’s aggression against Ukraine, which he has repeatedly supported. It is whatever the centre of world capital and its allies — in the Milne worldview, located in the United States, its European allies and Israel — does.

If Seumas Milne is no longer a Stalinist he has certainly not travelled far from Stalinism. What is most worrying is that on Milne’s appointment, Corbyn’s own campaign stated: “Seumas shares Jeremy’s worldview almost to the letter . . . they sing from the same hymn sheet.”