Developments in Eastern Europe and the Soviet Union cannot be explained without taking into account the role of Pabloite revisionism in this region throughout the post-World War II period.
Pabloism, named after one of its main spokesmen, Michel Pablo, emerged as a revisionist tendency within the Fourth International in the wake of the war. Expressing the interests of a growing layer of the middle class that benefited from the post-war restabilization of capitalism and the suppression of the working class through its old bureaucratic leaderships, the Pabloites questioned the very legitimacy of the independent existence of the Fourth International. Whether in the Stalinist-ruled countries, the advanced imperialist countries or the oppressed colonial and former colonial countries, the Pabloites advanced a line that repudiated the founding principles of the Fourth International: above all, the need for the political independence of the working class and the building of the Fourth International as the world party of socialist revolution.
Completely abandoning the Trotskyist analysis of Stalinism, the Pabloites ascribed a revolutionary role to the Stalinist bureaucracy in Eastern Europe and Asia. They wrote off the working class as an independent force entirely, arguing that “objective social reality” consisted “essentially of the capitalist regime and the Stalinist world.”  Based on this assessment, the cadre of the Trotskyist movement had no independent role to play. Rather, the Fourth International was to be liquidated into whatever national mass parties of the working class and oppressed masses existed.
With regard to Eastern Europe and the Soviet Union, the Pabloites advanced the concept of the “self-reform” of the bureaucracy. The Fourth International’s call for a political revolution to overthrow the Stalinist bureaucracy, restore workers’ democracy and return to the program of international socialist revolution was turned by the Pabloites into its opposite. What they called the “political revolution” was to be accomplished not by the working class under the leadership of the Fourth International, but by a section of the Stalinist bureaucracy itself, which would supposedly enact reforms that would lead to a peaceful transition from Stalinism to socialism. The role of the working class (and the Trotskyist movement) was reduced to that of a pressure group, which would help push forward the supposedly reformist faction of the bureaucracy.
The Pabloite tendency was opposed by the orthodox Trotskyists in the Fourth International, led by the Socialist Workers Party (SWP) in the US. The Pabloites were expelled from the Fourth International through the formation of the International Committee of the Fourth International (ICFI) in 1953. In the founding document of the ICFI, the Open Letter, James P. Cannon, the leader of the SWP, restated the basic principles of international Trotskyism:
1. The death agony of the capitalist system threatens the destruction of civilization through worsening depressions, world wars and barbaric manifestations like fascism. The development of atomic weapons today underlines the danger in the gravest possible way.
2. The descent into the abyss can be avoided only by replacing capitalism with the planned economy of socialism on a world scale and thus resuming the spiral of progress opened up by capitalism in its early days.
3. This can be accomplished only under the leadership of the working class as the only truly revolutionary class in society. But the working class itself faces a crisis of leadership although the world relationship of social forces was never so favorable as today for the workers to take the road to power.
4. To organize itself for carrying out this world-historic aim the working class in each country must construct a revolutionary socialist party in the pattern developed by Lenin: that is, a combat party capable of dialectically combining democracy and centralism—democracy in arriving at decisions, centralism in carrying them out; a leadership controlled by the ranks, ranks able to carry forward under fire in disciplined fashion.
5. The main obstacle to this is Stalinism, which attracts workers through exploiting the prestige of the October 1917 Revolution in Russia, only later, as it betrays their confidence, to hurl them either into the arms of the Social Democracy, into apathy, or back into illusions in capitalism. The penalty for these betrayals is paid by the working people in the form of consolidation of fascist or monarchist forces and new outbreaks of wars fostered and prepared by capitalism. From its inception, the Fourth International set as one of its major tasks the revolutionary overthrow of Stalinism inside and outside the USSR.
6. The need for flexible tactics facing many sections of the Fourth International, and parties or groups sympathetic to its program, makes it all the more imperative that they know how to fight imperialism and all of its petty-bourgeois agencies (such as nationalist formations or trade union bureaucracies) without capitulation to Stalinism; and, conversely, know how to fight Stalinism (which in the final analysis is a petty-bourgeois agency of imperialism) without capitulating to imperialism.
Pabloism abandoned each and every one of these principles. Its program was liquidationism all down the line. Historically, it emerged at the very point when Stalinism entered its death crisis: 1953, the year of the split within the Fourth International, was also the year of Stalin’s death and the beginning of a series of mass working class uprisings throughout Eastern Europe that challenged the Stalinist bureaucracy. Three years later, the revelations of Khrushchev at the 20th Party Congress confirmed the Trotskyist analysis of the counterrevolutionary role of Stalinism.
In working to destroy the Fourth International, the Pabloites played a key role in propping up the rule of Stalinism and maintaining the political dominance of Social Democracy and the trade union apparatuses in the advanced imperialist countries. The Pabloites constituted a critical factor in the establishment and maintenance of the post-war capitalist order.
Whenever there was a direct challenge to the Stalinist bureaucracy from the working class in Eastern Europe, the Pabloite International Secretariat (IS) swiftly and aggressively intervened, sowing illusions in the “self-reform” of the bureaucracy and working to prevent the building of sections of the International Committee of the Fourth International. They thus consciously sabotaged the development of the political revolution by the working class against the bureaucracy.
This intervention assumed particularly stark dimensions in Czechoslovakia in 1968. In a tragic irony of history, a key role in the intervention of the Pabloites in Eastern Europe was played by Ernest Mandel, who had, while still an orthodox Trotskyist in the 1940s, played an important role in developing the Fourth International’s analysis of developments in Eastern Europe.
Once he had capitulated to Pabloism, however, Mandel became a pioneer of the theory of the “self-reform” of the bureaucracy. He explicitly articulated an orientation toward the nationalist wings of the respective Stalinist bureaucracies, writing:
The opposition within the CPs capitalizes on national feeling. The struggle for the “national road toward socialism” thus takes on there a highly progressive and revolutionary value, contrary to that in the CPs of the West, where it generally covers up a turn toward codified rightist opportunism. Gomułka in Poland, Nagy in Hungary, tomorrow perhaps Hernstedt or Ackermann in East Germany, by becoming in the eyes of the masses symbols of a struggle for national emancipation are creating favorable conditions for a renewal of popularity for the CP (through its “national” tendency) and permitting the political revolution under oppositional communist leadership to mobilize national feeling in its favor... 
The ever more unrestrained adaptation to and glorification of nationalist forces would become the hallmark of Pabloite intervention in Eastern Europe and the Soviet Union, from Gomułka, himself an ardent anti-Semite and Polish nationalist, to more extreme nationalist factions within the Soviet Union. Czechoslovakia was no exception. There, the Pabloites glorified the Dubček wing of the bureaucracy, which consciously worked to foster nationalist sentiments and divisions between the Czech and Slovak workers, while pushing for its “national road” to socialism, i.e., pro-capitalist reforms.
Making use of the possibilities for traveling to and from Czechoslovakia (almost 700,000 people traveled from Czechoslovakia to capitalist states from January 1968 to April 1969), the International Secretariat was able to establish close ties with Petr Uhl, who was to become one of Czechoslovakia’s leading dissidents.
Uhl had been to Paris in 1965 and 1967, where he had met Alain Krivine, a leader of the French Pabloites. In October 1968, Uhl, who was then working as a teacher at a Prague technical school, formed a group of between 50 and 100 people that was in political sympathy with the IS. They soon founded the Revolutionary Movement of Youth. In this they were assisted by Sibylle Plogstedt, who had come to Czechoslovakia as an exchange student. Plogstedt was a member of the West German Pabloite group GIM (Group of International Marxists) under Jakob Moneta. According to the biographer of Ernest Mandel:
Uhl and his comrades unleashed a storm of activity, including organizing the massive turnout for Jan Palach’s Prague funeral in January 1969. Palach was the student who had immolated himself in Wenceslas Square in protest against the Russians and died from his burns. Plogstedt requested Mandel to send a stencil machine quickly… With Jakob Moneta’s help, Mandel arranged to have the machine shipped to Prague. Uhl and Mandel met a few times in Berlin and discussed the challenges facing the Czech anti-Stalinist opposition. 
The government cracked down on Uhl’s group a few months later. Plogstedt, Uhl and several others were arrested. A year later, they were sentenced to jail (Plogstedt to two-and-a-half years, Uhl to four years.) Once released from jail, Uhl emerged as one of the leading dissidents in Czechoslovakia. He was an early signer of the famous Charter 77, one of the most important documents of the Czechoslovak and Eastern European dissident movement. In the years to come, he worked closely with Václav Havel. He helped edit the news bulletin of Charter 77 and contributed to the volume The Power of the Powerless, a collection of essays by leading Czechoslovak dissidents.
In his essay, “The alternative community as revolutionary avant-garde,” Uhl started by offering a quasi-Trotskyist assessment of the need for political revolution in Eastern Europe and social revolution in the West (without at any point mentioning either Trotsky or the Fourth International). He continued by promoting the Pabloite conception of the “self-reform” of the bureaucracy as the basis and starting point for political revolution, and the “self-management system” that had been advanced especially by Ernest Mandel as the model for a genuinely socialist organization in Eastern Europe.
Finally, Uhl insisted that the “alternative community,” not a political party of the working class, let alone the Fourth International, was the “revolutionary avant-garde” in the political revolution. This “alternative community” was to be politically undifferentiated. Uhl insisted on its “openness,” while praising “revolutionary Catholics” in the Czechoslovak “underground.” He then wrote:
Only a community consisting of both informal and institutionalized groups with experience in action and practice can become the new type of avant-garde that can genuinely express the main interests of oppressed society. In such a revolutionary avant-garde, various alternative associations can join forces informally. Such revolutionary associations do not exclude the organizing of various groups, and perhaps even of political parties. On the contrary, such groups, often in connection with other groups, may play an important role in the anti-bureaucratic struggle. 
This kind of argumentation, completely devoid of any class analysis of social and political tendencies, opened the way for collaboration not just with sections of the bureaucracy itself, but also with very right-wing, nationalist forces. Indeed, the open collaboration with nationalist and even fascist forces in the politically amorphous dissident movements throughout Eastern Europe and the USSR, and especially during Gorbachev’s perestroika, was to become a hallmark of Pabloite politics.
With this kind of “anything goes” line, the Pabloites and their helpers in Eastern Europe propped up the pro-capitalist tendencies within the dissident movement, which challenged the Stalinist bureaucracy from the right, and helped provide the ideological and political basis for the restoration of capitalism. Meanwhile, left sections of the intelligentsia and the working class were disoriented and subordinated to right-wing forces.
Virtually all of the chief Pabloite representatives and collaborators, whether in Czechoslovakia, Poland or the USSR, ended up as advisors to the Stalinist bureaucracy in the process of capitalist restoration in the late 1980s and early 1990s. Petr Uhl’s role as advisor to the “Civic Forum” of Václav Havel , which negotiated the reintroduction of capitalist property relations and the destruction of the Czech and Slovak Socialist Republics at the “Round Table” in the fall of 1989, was only one example of many. (See also: Capitalist restoration in Russia: A balance sheet).
To be continued
 Quoted in: David North, The Heritage We Defend. A Contribution to the History of the Fourth International, Mehring Books 2018, p. 184
 Quoted in Ibid., pp. 309-310
 Jan Willem Stutje, Ernest Mandel. A Rebel’s Dream Deferred, Verso 2009, p. 176
 Petr Uhl, “The alternative community as revolutionary avant-garde” in The Power of the Powerless. Citizens against the State in Central Eastern Europe, ed. by Vaclav Havel et al. Routledge 2016, p. 197