Critics within/around the DSA (US) sometimes speak about "wreckers" (mostly in reference to people playing identity politics to disrupt organising), but even in general among the US Left there is a basic awareness about the reality of things like COINTELPRO, etc.
The WSWS has re-emphasised the role of spies in Trotsky's entourage and their possible role in his assassination. Incidentally on Trotsky, I want to publish the following strange info (from email correspondence, so forgive my indiscretion). In a recent email the historian Getty claims that many years ago, when checking Trotsky's Harvard papers, he found that file 15765 was empty, and he believes its contents were purged (only the file's description apparently remaining). However, when I checked the site it says this file contains 3 pages: [Notes on various Russian agents and suspects]. TS.; [Coyoacán, ca 1940]. 3s.(3p.)., 1940 https://hollisarchives.lib.harvard.edu/repositories/24/archival_objects/2042383
Ideally someone should verify whether the file at the archive today is still empty, as Getty now remembers it being in the 1980s when he did his research (or whether Getty now just suffers a false recollection – leaving aside the possibility that the file had been emptied, but now is full again). The title appears to show that Trotsky himself did have suspicions about spies among his group.
But still, perhaps a few mainstream Pabloist/reformist-anarchists, trying to be "respectable", will still try to dismiss this as paranoia from crazy Marxist sects. So here is a piece by a centrist voice, a leading theorist in the SPA (Socialist Party of America) in October 1909, the American Marxist writer Algie Simons, who talks about wreckers: https://archive.org/details/SocialistStagnation/page/n5/mode/2up Simons notes the rapid growth of the SPA membership, and yet, it's felt that there is a crisis in the SPA. He considers one cause to be wreckers or spies in the SPA. I quote the entire relevant passage in Simons. I think it aligns with the "parasitism"-theses by the ICC:
"Another explanation, which at first sounds almost fantastic, has been offered. It is that the Socialist party has been filled with spies, not to seek out secrets (for we have none), but to actively disrupt the movement. When this explanation was first suggested I laughed at it, as indeed did nearly all the other best informed Socialists. But little by little what seemed like evidence accumulated until today I do not think I am wrong when I say that nearly every one who has had to do with the management of the national organization, or is familiar with the whole situation has come to agree that there is at least a strong probability that secret agents play a part in the disrupting work going on within the party.
The more the facts are examined the less improbable this explanation appears. Every one knows that the unions are honey-combed with spies. Single agencies employ thousands of men for this purpose. We know that the capitalists have come to recognize that the only force that is really threatening exploitation is Socialism. They need only to look to Europe, with which most of them are familiar, to confirm their fears.
Moreover, we have very direct evidence that they do recognize the menace of Socialism. The Civic Federation is undoubtedly the organized expression of the keenest, most far-seeing and unscrupulous capitalism in America. Its policy of corrupting the union movement, tricking the leaders of labor into the position of bell-wethers by which to lead their followers to the slaughter, the very men who compose it, all testify to the truth of this statement. This organization has definitely declared war upon Socialism. It has called for a fund of fifty thousand dollars to be used in fighting- Socialism. We know that it has gathered around it and is supporting the most disreputable gang of literary prostitutes that this country has ever known, and is using them in its war upon Socialism. We know that those who have been driven out of the Socialist party because ef dishonesty and immorality find a ready welcome from this defender of bourgeois morals. We know that those who manage it are adepts in the use of spies. We know that they have long been using them for other purposes. Is it, then, too fantastic a thing to suggest that some of the funds which the Civic Federation is spending, in its war upon Socialism are used in the hiring of spies to act as agents of disruption within the Socialist party?
Once within the party the course of conduct for a spy is plain. He would counterfeit the fanatic. He would be a radical of the radicals. He would be intolerant and most vehement in his denunciations of capitalism. He would be extremely active in party work and very ready to show his devotion to Socialism.
So far there would be no way by which to distinguish the spy from the sincere and faithful fanatic (and I would be the last to say that the time will ever come when the Socialist movement can afford to dispense with him whom we call the fanatic).
If the spy did nothing more than this he would do little damage. But he is there to do something more. He will naturally desire posts of authority. He will be especially eager for administrative positions. He will try to create factions and to make himself the candidate of a faction. He will cling to any official position he may secure and declare that he holds it in defense of a principle. He will foster everything that makes for divisions within the party. He will be ultra-orthodox and demand the expulsion of all who do not agree with the faction from which he derives his power. He will become a professional proletarian, skilled in all the arts of the demagogue. He will attack any constructive work undertaken within the party, or by any member of the party. He will pretend to veil such attacks behind questions of principle and seek to arouse a factional struggle on every point. For in this way two objects are accomplished: the party is disrupted and the work of Socialist propaganda is hindered. He will foster all jealousies within the organization, and seek to destroy the effectiveness of any one who may be accomplishing anything for Socialism. He will play upon the petty vanities of the incompetent and the ignorant and seek to inflame them against those who are capable and willing to accomplish any work of agitation and education. When he is trusted with party work he will permit its enterprises to fail through carelessness, or even apparent incompetence.* (Note. — Since this has been in manuscript I have shown it to a number of Socialists. On reading this portion the almost inevitable exclamation has been, "I see you are hitting ....," but always a different name. At least five such names have been so inserted by persons who thought they recognized the individual described. There could hardly be any stronger proof of the existence of the type, or of the fact that no individual is especially selected for description.)
Whoever is doing these things and displays these characteristics within the Socialist party is doing the work of an agent of capitalism. Whether he is receiving the pay or not is unimportant. In fact, it is a debatable question as to which is the more dangerous to a successful organization — the cheap fanatical politician who sincerely believes with regard to the Socialist party as Baer does of the coal mines, that "God in His infinite mercy has confided it to his care," and who through petty jealousy and narrow demagoguery clings to an official position, or the paid spy of capitalism, who does these things as part of a general plan.
In either case such a person should be a marked man, to be gotten rid of by the organization as quickly as possible. The Socialist party does not need guardians in its official positions. It does not want leaders of factions there. What is needed in the offices of state and local secretaries is men who know how to reconcile differences within the party and to utilize all forces for Socialism. The place to settle questions of principle is in legislative bodies such as state and national and delegate committees or in branch and local mass meetings. The less that administrative offi- cials have to say in such gatherings the better.
The party official who starts out to reform the party, who organizes factions or becomes the creature of one, who attacks those who are working for Socialism instead of utilizing their work and fitting it into a part of the general party work, is either incompetent or worse, and deserves no consideration in either case. If this rule is followed and all such persons are speedily relegated to private life, then the spy can do us no harm, because it is only through these methods that disruption comes.
Practically every one of the localities in which the party is now disorganized has one or more persons who display the characteristics described. It matters very little whether these persons are really paid agents of capitalism, or simply very cheap party politicians and loud-mouthed demagogues, they should be gotten rid of as promptly as possible.