Both the invasion of Poland and the earlier Molotov-Ribbentrop had caught the global communist movement flat-footed and created ideological confusion and disorientation. One of the most animating ideological features of the communism in the 1930s was that communism was locked in a global struggle with fascism. The various iterations of the popular front reflected this ideological conceptualization of international politics. Various communist parties, with the approval of Moscow, entered into political coalitions with like-minded "bourgeois" parties to serve the greater good of combating fascism. The participation of their non-communist political allies in the Munich Pact had soured many European communists on the viability of a popular front strategy, but Hitler's invasion at first seemed to an opportunity to rekindle a united struggle against fascism. Harry Pollitt, the Secretary General of the Communist Party of Great Britain, supported Britain's declaration of war on Germany in a pamphlet published on 14 September claiming,

The Communist Party supports the war, believing it to be a just war. To stand aside from this conflict, to contribute only revolutionary-sounding phrases while the fascist beasts ride roughshod over Europe, would be a betrayal of everything our forebears have fought to achieve in the course of long years of struggle against capitalism.

In France, the PCF's representatives within the parliament voted for war credits in September 1939 and there was a widespread sense that war with Germany would spark a rapprochement with the Soviet Union.

Moscow instructions to the Comintern that this was an imperialist war and there was no functional difference between bourgeois capitalist states and fascist states created much confusion within communist leadership and many communist parties had to backpedal on their prior support for the war. Some communist leaders like Pollit refused to tow this pro-German line, but much of the communist leadership dutifully followed Moscow's lead and attacked the imperialist war. In regions where anti-imperialism was a staple of communist rhetoric such as Ireland or East Asia, this new course was easier for the leadership to countenance. Yet for many within the communist movement, supporting Germany by attacking the British and French was a bitter pill to swallow. Various communist parties enacted a series of internal purges of disloyal members unwilling to accept this turn of events. Pollit, for example, had to resign his secretaryship for a more pliant leader. Adding to these internal problems, communist parties found themselves attacked from without for their allegedly pro-Hitler stance. The French government banned the PCF in late September and forcibly dissolved communist trade unions, dismissed PCF officials, and jailed militants. All of this contributed to a significant outflow of party membership as internal and external pressures coupled with the unpopularity of the pro-German orientation to create a broad disillusionment with the Soviet Union. Speaking from Norway, the socialist emigre Willy Brandt summed up a popular attitude of the left to the Pact in an editorial :

The attitude of the socialist movement towards the Soviet Union today must be considered against this background. Relations have changed almost beyond recognition. It is hardly a novel situation to find the leaders of the Soviet Union in a state of outright war against the socialist movement. It has happened before. But today the whole movement is obliged to stand up and fight, and draw a clear dividing line between itself and the Soviet Union. It is not the socialist movement but the Soviet Union which has changed. It is not the socialist movement but the Soviet Union which has entered a pact of friendship with Nazism. It is the Soviet Union which stabbed Poland in the back and initiated the war against Finland.

Brandt's invectives against the USSR demonstrates the real disappointment that many of fascism's victims felt because of the pact. The French-based Italian Anti-Fascist Alliance collapsed and some the Italian communist leaders like Romano Cocchi openly broke with the official Comintern line. German KPD exiles in Western Europe found themselves jailed first both by the Allies and then by the German occupation, making the Soviet-based leadership of Pieck and Ulbricht much more dependent on the goodwill of their Soviet hosts. Similarly, Spanish exiles in the Soviet Union had to walk a fine line between their public support for the Soviet Union and the movement's apparent abandonment of antifascism.

The German invasion of the Soviet Union provided a much needed restoration of ideological clarity for the global communist movement. The pact and the subsequent invasion of Poland could now be more easily rationalized as a Fabian tactic and the Soviet alliance with the US and Britain finally made for a functional popular front. However, the damage the Molotov-Ribbentrop Pact had done to Soviet prestige was quite significant. As Brandt's editorial aptly pointed out, the Soviet's use of standard geopolitical tactics had rendered it into an ordinary nation-state. This conventional Soviet Union stood in stark contrast to the utopian entity that it was common in left-wing discourse during the interwar period. The disenchantment created by the Pact inspired both Koestler's novel Darkness at Noon and Orwell's 1984 and Animal Farm, widely-read novels which popularized the shortcomings and hypocrisy of the Stalinism for many in the postwar era. The end of a utopian vision of the USSR made it much easier for Western European and global communist parties to strike their own path in the aftermath of the various postwar crackdowns like Hungary.

Sources

Eley, Geoff. Forging Democracy The History of the Left in Europe, 1850-2000. Oxford: Oxford University Press, 2002.

Furet, François. The Passing of an Illusion: the idea of communism in the twentieth century. Chicago: University of Chicago Press, 1999.

Kirschenbaum, Lisa A. International Communism and the Spanish Civil War: Solidarity and Suspicion. New York: Cambridge University Press, 2015.