Some folks might correctly remember that the SI membership included well known politicians like Josef Stalin, Friedrich Engels, V.I. Lenin, and Leon Trotsky. That probably explains why so many of the planks of the Communist Manifesto(5) are included in the Democratic Party's platform and are the expressed goals of the Congressional Progressive Caucus. Not quite accurate. The Social Democrats are the Second International and afilliated with the Euro-left. The Communitst Party of the Soviet Union was the Third International. Trotsky founded the Fourth International. The First International was crushed back in the 19th century.
The Second International survives because its less revolutionary approach seems less threatening.
well done.
Comintern Bump, Stalin's old organization controled the 2nd international as well as the 3rd. In the end Kautsky lost the argument.