Entryism re-entered Labour’s lexicon in the summer of 2015 as thousands of members and supporters of other parties (among them Greens, Trotskyists and Tories) sought to vote in the leadership election. But the term historically refers to a far greater degree of strategy and organisation.
The founding example of entryism was provided by Leon Trotsky and the “French turn”. In 1934, the Russian revolutionary persuaded his supporters to dissolve the Communist League into the Socialist Party in order to maximise their influence. The term has since been applied to any group that enters a larger organisation with the intention of subverting its policies and objectives.
Labour’s most notable experience of entryism came with the Trotskyist Militant, which won control of the party’s youth wing (Labour Party Young Socialists) and a number of constituency parties. After its proscription by the National Executive Committee in 1982, hundreds of the group’s members were expelled during Neil Kinnock’s leadership, including two MPs (Terry Fields and Dave Nellist). Len McCluskey, the Unite general secretary, was a Militant supporter though never formally joined.
“Operation Ice Pick” was the name given to Labour’s efforts to prevent entryists from voting in the 2015 leadership election, after the means of assassination used against Trotsky. Those barred included members of the Socialist Party, the successor group to Militant. The pro-Corbyn organisation Momentum has similarly banned outsiders from joining after MPs warned that it could become a vehicle for entryism.
Responding to charges of infiltration, Jeremy Corbyn said: “The entryism I see is lots of young people who were hitherto not very excited by politics, coming in for the first time.”