In this chapter, Orwell delineates the difference between the PSUC (the Partido Socialista Unificado de Cataluna) and the POUM (Partido Obrero de Unificación Marxista), the latter of which he was a member. Essentially, the PSUC was composed of communists who favored the Stalinist approach to the Spanish revolution, as opposed to the Anarchist approach, supported by Trotsky.
Stalin opposed the proletariat struggle for relevance in Spain because he was more concerned about preserving Soviet power amid the growing fascism represented by Mussolini's Italy and Hitler's Germany. Stalin's aid to the Spanish government was predicated on promises that the left-wing government would quash any revolutionary fervor on the part of the Anarchists. The Soviets feared anarcho-syndicalist control of Spain, which was intent on collectivizing all industry. Meanwhile, the Spanish government itself was against any collectivization because of foreign investment in the country. Once the trade unions got in the way, the return on foreign investment would be decimated.
The Barcelona Traction Company, for instance, represented ten millions of British capital, and meanwhile, the trade unions had seized all the transport in Catalonia. If the revolution went forward, there would be no compensation or very little; if the capitalist republic prevailed, foreign investments would be safe.
So, this is how it came to be that Orwell described a political alliance between the Soviet Union and the Spanish government as a partnership predicated on the achievement of 'bourgeois democracy' and not 'workers' control.' According to Orwell, the Communist Soviet Union saw military alliances as a lifeline against the Fascist threat. So, both France and Spain had to be, essentially, strong capitalist-imperialist countries in order to bolster the Soviet position. That was why the Soviets worked tirelessly to suppress the proletariat revolution in Spain. The Communist PSUC viewed the Anarchist, collectivist utopia as an impediment; in the PSUC's opinion, divisions caused by the conflict between bourgeois and proletariat could be used to advantage by the Fascists (against the Communists). Orwell tells us that:
The Communist's emphasis is always on centralism and efficiency, the Anarchist's on liberty and equality.
The Communist emphasis on doing away with 'revolutionary chaos, (to) speed up production, militarize the army' appeared to be the main reason the PSUC held off on supporting the working-class revolution in Spain. Basically, central control of the capitalist machine in Spain was a Communist goal: in Stalin's view, strong military allies were an essential tool in his war against the fascists (Germany and Italy). As such, the Anarchist, collectivist mentality would not have ensured the creation of a vibrant and powerful military machine, worthy of annihilating the Fascist threat.