movement to be discredited while the Bolsheviks appeared more independent and patriotic, driving former Imperial military leaders into joining the Bolsheviks instead. The Allied intervention helped to bolster the Bolsheviks, as they also successfully used this to attack the Whites and paint themselves in a positive light. Allied withdrawal The Allied Powers withdrew in 1920. The Japanese military stayed in the Maritime Provinces of the Russian Far East until 1922 and in northern Sakhalin until 1925, following the signing of the Soviet–Japanese Basic Convention in Beijing, in which Japan agreed to withdraw its troops from Russia. In return, the Soviet Union agreed to honor the provisions of the Treaty of Portsmouth. Assessment by historians In 1957, Frederick L. Schuman wrote that the consequences of the expedition "were to poison East-West relations forever after, to contribute significantly to the origins of World War II and the later 'Cold War,' and to fix patterns of suspicion and hatred on both sides which even today threaten worse catastrophes in time to come." For Soviet leaders, the operation was proof that Western powers were keen to destroy the Soviet government if they had the opportunity to do so. Modern historian Robert Maddox summarised, "The immediate effect of the intervention was to prolong a bloody civil war, thereby costing thousands of additional lives and wreaking enormous destruction on an already battered society." Historian John Thompson argues that while the intervention failed to stop the Bolshevik revolution in Russia, it did prevent its spread to central Europe: However, it did succeed in so thoroughly engaging the forces of revolutionary expansionism that the countries of war-torn eastern and central Europe, potentially most susceptible to the Bolshevik contagion, were able to recover enough social and economic balance to withstand Bolshevism. The interventionist attempt left an ugly legacy of fear and suspicion to future relations between Russia and the other great powers, and it strengthened the hand of those among the Bolshevik leadership who were striving to impose monolithic unity and unquestioning obedience on the Russian people. Legacy According to Sheldon M. Stern, Stalinist propaganda later portrayed the Allied intervention as a U.S. military invasion of Russia while denying or minimizing the American famine relief effort that saved millions of Russian lives during 1921–1923. Winston Churchill, who had been the most prominent supporter of a campaign to remove the Bolsheviks from power, long lamented the Allies' failure to crush