They argue and split hairs, they fight and break heads, they work together and destroy liberty because they all travel to the same soul-crushing destination. As far as liberty-loving anti-communists are concerned, communists and socialists -- and "democractic socialists," Fabians, progressives, Alinskyites (not to mention most Democrats and an awful lot of Republicans), etc. -- believe in the same centrally planned, varyingly totalitarian vision for America that the founding fathers would have had to declare independence from all over again.
To that point of ideological convergence, a couple of quotations
The first is from Rene Wormser, a renowned lawyer specializing in estate planning and taxation who served admirably as the general counsel of the Reece committee, the second of two 1950s congressional committees investigating the Marxist/socialist/communist/progressive/etc./etc./etc. subversion of the great American foundations, which, of course, undergirded the subversion of our educational institutions.
Reflecting on both committees' work, Wormser wrote the following on pp. 177-178 of his extremely important book, Foundations:
The two recent Congressional investigations were largely concerned with "subversion." The Cox Committee interpreted this term to include only international communism of the Stalinist brand and organized fascism. The Reece Committee, in the course of its work, came to give the term broader or deeper meaning. Neither investigation established sharply, however, the characteristics of Communist activity which would be clearly held to be subversive. In the public mind, the term "subversion" is generally confined to Moscow-directed Communist activity, or that of domestic Communists allied in an international conspiracy. The emphasis on a search for organized Communist penetration of foundations absorbed much of the energy of the investigators and detracted somewhat from the efficacy of their general inquiry into "subversion."
There are varieties of Communist sectarian programs and propaganda of a dissident nature, aside from those directed from Moscow. A follower of Trotsky's brand of communism may be no less a danger to our society because he opposes the current rulers of Russia. It is likely that there are more Trotsky followers in the United States than followers of the Kremlin. Even among the formerly orthodox supporters of the Party line, there has occurred a mass conversion to a domestic form of the Communist theory and method. Moreover, it is difficult to mark the line beyond which "socialism" becomes communism." The line may be between methods of assuming power, comrnunism being distinguished from other forms of socialism by its intent upon establishing a dictatorship of the proletariat. But this line is by no means clear. Socialism has the same ends as communism, though with an allegedly democratic approach, The Communist Manifesto of 1848 is the basis of all socialist parties the world over. Marx himself did not distinguish between socialism and communism.
To this point of emphasis on the ideological convergence between socialism and communism made by anti-communist Wormser it is well worth adding a relevant quotation from the famed British Fabian/socialist/Marxist (see what I mean about interchangeability?) Harold Laski, friend and couselor to FDR among everyone else on the Left in first half of the 20th century.
In his 1947 Introduction to Marx and Engels' "Communist Manifesto," Laski address the "communist" in the Manifesto:
Why "communist" and not "socialist" Manifesto? Obviously, in the first instance, because it was the official publication of the Communist League. We have little other evidence on which to base speculations. It was possibly the outcome of a recollection of the Paris Commune, an institution to which all socialists did homage. It was possibly a desire to distinguish the idea for which they stood from socialist doctrines which they were criticizing so severely. The one thing that is certain, from the document itself, is that the choice of the term "Communist" was not intended to mark any organizatinal separation between the Communist League and other socialist or working-class bodies.
On the contrary, Marx and Engels were emphatic in their insistence that the Communists do not form a separate Party and that they ally themselves with all the forces which work towards a socialist society.
Seeking or depending on distinctions among them all has the effect of blinding the anti-communist to their common aggression.