It seems quite incompatible with recorded history.
One expert verdict of "this is made-up" is already found in the question. Proving a negative is not easy. But there is plenty of circumstantial evidence to support that negative.
The language used, the political connections drawn, and most important: the date always used in this unsourced propaganda from anti-communists lessen the probability and plausibility severely.
At the centre of World Revolution, Stalin controlled large funds for communists outside the Soviet Union and guided the theoretical and political aims, goals, and strategies of those depending on Soviet aid for their political work. And Stalin was in the habit of ordering fierce agitation in other countries opposing the Soviet Union, especially in war, but ordering silence and cooperation in countries allied. This is what happened in Germany from 1939–1941, when the then underground communists of the then prohibited KPD lost the incentive to oppose Naziism — as Nazi-Germany was now the friend of the worker's paradise, and after Operation Barbarossa when German communists were again instructed to do the utmost in trying to bring down the fascists.
For the communist party in the US:
The party dropped its peace program and demanded American aid for the Soviet Union and American intervention in the war. After Pearl Harbor, the CPUSA endorsed Roosevelt's war policies, called for a quick American invasion of Europe to relieve Nazi pressure on the Soviets, and vehemently denounced any interference with the war effort as treasonous. These policies allowed the rebuilding of many of the Popular Front relationships destroyed during the period of the Nazi-Soviet Pact. The heroic Soviet resistance to the Nazi army also lessened the pervasive anticommunist sentiment of the American public.
Released from prison in 1942 as a symbol of goodwill toward America's Soviet allies, Earl Browder became convinced that the Soviet Union's wartime alliance with the United States and Great Britain was permanent. Emboldened by the dissolution of the Comintern in 1943, Stalin's gesture to his Western allies, Browder dissolved the CPUSA in 1944 and reformed it as the Communist Political Association, intending to make Communists the left wing of the Democratic party. He announced that socialism would not be on the American agenda in the foreseeable future, a step that disconcerted some members of his own party.
— Harvey Klehr, John Earl Haynes, and Fridrikh Igorevich Firsov: "The Secret World of American Communism", Yale University Press: New Haven, London, 1995, p. 11.
This is of course circumstantial evidence. Especially in light of the historic record of chaotic incompetence of the American communists. Whether there was such a directive given out cannot be excluded completely from the above.
In 1943 Wolfgang Leonhard, a young German attending a Communist International (Comintern)school for foreign Communists near Ufa, a city 750 miles east of Moscow, received an unusual assignment. The Comintern's archives had been transferred to Ufa when the Nazi army was threatening Moscow, and Leonhard was among a group of students given the task of putting the chaotic archives into order. His assignment was to organize the records of the American Communist party. In his memoir written in 1958, a decade after his break with communism, Leonhard noted:
The Communist Party of the U.S.A. was readily conceded first place for chaos and confusion. The sacks belonging to my American comrades contained not only whole bundles of Party documents which had simply been stuffed in without even a file-cover being put round them, but also the remains of cinema advertisements, old numbers of the New York Times, broken pencils and every kind of rubbish that had not the slightest connection with the archives…
There were so many things that I would have liked to have read – protocols of sessions of the Central Committee, struggles with the factions, justifications for the expulsions of leading Party officials-but unfortunately there was not the slightest possibility. I had to open the sacks, put the material in folders, and write on the outside "Trade Union" or "Miscellaneous" or "Party 1921–1923''at the pace of a Stakhanov. With every day that passed, we were urged more and more often to pay less attention to accuracy than to speed.'
ibid., p. 4.
But this remote possibility of a subaltern faction giving out this order from the claim, or just something resembling it, doesn't alter the fact that the date of 1943, the wording, the strategy outlined and the attribution "communist headquarters" are not plausible.
As this area of investigation was of the highest interest for American anti-communists, some form of evidence should surely be found. What committees and the FBI did find looked like this:
In addition to its investigation of alleged Japanese subversion,
the Committee connected the Japanese problem to the ubiquitous
Communist menace. Basing its conclusions largely on the editorial
policy of the Communist newspaper, The People's Daily World,
the Committee summarized the Communist Party line in 1942:
All Communists are ordered to minimize the Japanese danger. All large military efforts in the United States must be directed to Europe. Our immediate task is the defeat of Hitler and the protection of the Soviet Union. Smear anyone who advocates major activities against Japan at the present time. Our historic course with Japan will be determined at the conclusion of the war with Germany.
Meanwhile our traditional role as the champion of racial equality must be maintained.26
Footnote 26: Second Report, p 60 (Fully cited as: California Legislature, Report: Joint Fact-Finding Committee on Un-American Activities in California. With the report for 1948, substitute "Senate" for "Joint" Fact-Finding Committee. Henceforth to be cited as First Report, Second Report, etc. The reports noted above are: First Report (1943); Second Report (1945); Eleventh Report (1961); Twelfth Report (1963); Thirteenth Report (1965); and Thirteenth Report Supplement (1966).
— Robert L. Pritchard: "California Un-American Activities Investigations: Subversion on the Right?", California Historical Society Quarterly, Vol. 49, No. 4 (Dec., 1970), pp. 309-327. (jstor)
Note the date and that it is again an interpretation done by an interested side. Some of these reports are on archive org, and they use the word "smear" a lot. Often it seems as if the meaning has changed.
Apart from the assertion in They Never Said It that
Researchers in the Library of Congress have been unable to locate any such 'directive'; nor do specialists in Soviet affairs regard it as authentic.
We also have to include prosecutors under the Smith act and federal agents to those who were looking to find exactly that kind of 'evidence':
The FBI had compiled a list of 200,000 persons in its Communist Index; since the CPUSA had only around 32,000 members in 1950, the FBI explained the disparity by asserting that for every official Party member, there were ten persons who were loyal to the CPUSA and ready to carry out its orders.
And this relative amount of infiltration became ever greater, when the CPUSA membership was down to 5000 at the end of the fifties:
Following orders from the Kremlin, Hoover explained, Levison was guiding Dr. King, thus affecting the course of the civil rights movement. In a hearing, he described the party in the United States as “a Trojan Horse of rigidly disciplined fanatics unalterably committed to bring this free nation under the yoke of international communism.” He may well have been jousting with his boss, for the attorney general had recently said that the American Communist party “couldn’t be more feeble and less of a threat, and besides its membership consists largely of FBI agents.” Kennedy had been horrified to discover that Hoover had assigned over one thousand agents to internal security, merely a dozen to organized crime
— Curt Gentry: "J. Edgar Hoover: The Man and the Secrets", W. W. Norton & Company, 2001.
Concerning the language used in the supposed order:
The American communists of that era do indeed use the word 'obstructionists' a lot. But they also use the word 'fascist' a lot. For one simple reason: they saw themselves as real enemies of those real fascists. Directing their members to just call anyone 'in their way' 'a fascist', as that has "already a bad smell" is counter to their ideology. The claim implies that 'descent conservatives' is not an oxymoron, but something the communists also believed, only they were sneakily subverting their own believe with just relabeling those 'decent men', those non-fascists, in public?
That doesn't make much sense.
The communists either saw them as fascist or maybe they needed to be told from higher ups that they needed to believe 'them' to be fascists. But not to 'lie and apply an unreal label' just for "smear tactics". It's just illogical. They either saw someone as being an antisemite or not. They did not apply a label like that to 'make someone look like an enemy'. They saw them as enemies. For real.
If communists were told 'what to think', or how 'we understand the world, and you need too', then we have a few documents that allow us a peek into that:
The Communist was the primary monthly theoretical journal of the Communist Party that began publishing in 1927. Last published in Dec 1944.
In that we read for 1943 a lot about how obstructionists are "Munichites", secret or open "defeatists" — by way of their insistence on 'capitalist freedoms' when it was time to fight nazism. Which this paper analysed as 'capitalists want Germany to win the war — to avoid the US becoming communist as well'.
Example:
The main burden of their declaration was in favor of closer relations with the poll-taxers and in a continuance of those obstructionists tactics which had disgraced the last session of the 77th Congress. Among other things, the uneasy majorities by which many of these gentlemen went into office in the last elections, however, is evidence of the fact that unity of action by labor and the people can help influence the Administration to a bolder position against the obstructionist camp. The President's message made a beginning which labor and the people can make certain will be carried for ward with even greater vigor and consistency. […]
It is regrettable, under such circumstances, that the President did not indict these connivers at defeat and their "business-as-usual" allies and camp followers for the damage they have done and are doing to our nation's war effort. This he could have done, for instance, by reminding Congress and the people of what harm these obstructionists had wrought to the war effort by their undermining of his seven-point program for economic stabilization in the 77th Congress.
— Louis F. Budenz: "The President's message to Congress", The Communist, No2, Feb 1943, p. 157–165.
And in March only one mention of obstructionists appear:
The obstructionist cabal must be challenged, and the challenging can be done only by the President and all those in Congress and in the country, irrespective of party affiliation, for whom winning the war comes first.
In April:
Another fruitful field of Congressional obstruction of the national war effort has to do with the country's general economy. What is required in the United States in order to bring production up to its maximum and to avoid the danger of inflation is the adoption of a centralized war economy, much along the lines of Great Britain.
Perhaps the closest one can get in trying to align articles from "the Communist" to the claim is found in
This expresses itself as increasing revulsion from the idea of independent nationhood which is seen as the breeding ground of "communism." (The Hearst press has recently warned that "patriotism can become communism.") Defense of the nation evokes, as a military necessity, the forces of democracy, in all classes in varying degrees, and compels political collaboration with the working class of a kind which strengthens its national role.
An increasing readiness to sacrifice the achievements of the nation's entire national development marks the outlook of the Herbert Hoover- Martin Dies-Senator Wheeler types, who are evolving into the modern, more virulent expression of the Copperhead-that is, into the Lavalman.
This is what the war leadership of the country, President Roosevelt, the labor movement and the population in general need to grasp clearly - that a new class of traitor is breeding inside America, that it is a definite group moving toward betrayal of the nation to Nazi Germany because it fears that resistance to Nazi Germany will produce "communism" in the United States.
Fear of "communism" (excited deliberately also by the Goebbels propaganda) has suppressed in this group its sense of national self-preservation.
It is still a serious defect of the Government's internal policy that it tends to accept the viewpoint of the appeaser press which describes the enemies of the war effort as "critics."
President Roosevelt's fighting message to the new Congress was weakened by this hesitation in striking
out at the fifth column operating against him, and by a failure to summon the nation to struggle against it.[…]
Delay in opening this struggle will be costly, as it was costly to Lincoln. The nation, and the labor movement (which has its own Copperheads in such persons as John L. Lewis), need to develop a clear policy of united struggle against the defeatists. The achievement of this is, indeed, a precondition to destroying the nation's Axis enemies.
— Milton Howard: "Lincoln, Roosevelt, And The Fifth Column", The Communist, No. 2, Feb 1943, p. 135–145. (PDF)
That it is the claim's year of 1943 is then doubly doubly curious, as we do have quite a few, formerly secret 'directives' from some party head quarters. In this case, making up a picture slightly different than what the claims wants believers to think:
The formality of having notified the affected parties met, the Politburo of the Soviet party convened on 21 May in Stalin’s office with Dimitrov and Manuilsky present. Molotov read out the text of the decree of the ECCI Presidium on the dissolution of the Comintern. Mikhail Kalinin, a member of the VKP(b) Politburo and chairman of the Presidium of the Supreme Soviet of the USSR, favored moving the center of the Comintern to another place, such as London. This suggestion was received with laughter. Stalin explained:
Experience has shown that in Marx’s time, in Lenin’s time, and now, it is impossible to direct the working-class movement of all countries of the world from a single international center. Especially now, in war-time conditions, when Com[munist] Parties in Germany, Italy, and other countries have the tasks of overthrowing their governments and carrying out defeatist tactics, while Com[munist] Parties in the USSR, England, America, and other [countries], on the contrary, have the task of supporting their governments to the fullest for the immediate destruction of the enemy. We had overestimated our forces when we created the CI and believed that we would be able to direct the movement in all countries. That was our error. The further existence of the CI would discredit the idea of the International, which we do not desire.
The Soviet dictator offered one additional reason for dissolving the Comintern, which he admitted “is not mentioned in the resolution. That is the fact that the Com[munist] Parties making up the CI are being falsely accused of supposedly being agents of a foreign state, and this is impeding their work in the broad masses. Dissolving the CI knocks this trump card out of the enemy’s hands. The step now being taken will undoubtedly strengthen the Com[munist] Parties as nat[ional] working-class Parties and will at the same time reinforce the internationalism of the popular masses, [an internationalism] whose base is the Soviet Union.” The resolution was then unanimously adopted and published in Pravda the following day.
— Fridrikh I. Firsov, Harvey Klehr, & John Earl Haynes (eds): "Secret Cables of the Comintern, 1933–1943", Yale University Press, 2014.
Just when American communism practically ceased to exist as an organised entity, something like a last standing order poisoning America is given out, secretly, but miraculously uncovered by patriots, then read out constantly for decades in all its internal inconsistency and absurdity as 'proof' for: the paranoia of the cold war 1950s?