"Lenin’s great disappointment with spreading Communism abroad occurred in the summer of 1920. In April of that year, Poland, eager to forestall the reemergence of a strong and imperialist Russia, had made common cause with Ukrainian nationalists and invaded the Soviet Ukraine with the aim of detaching it from Russia. The invasion failed to ignite an uprising in the Ukraine, and the Polish armies soon found themselves in full retreat. As the Red Army approached the borders of ethnic Poland, the Politburo, the directing organ of the Communist Party, had to decide whether to stop or to continue advancing westward. Opinions were divided but Lenin insisted on offensive operations, and as by now was always the case, he had his way. He felt certain that both Germany and England were ripe for revolution, which the appearance of Communist armed forces on their borders would help ignite. In the summer of 1920, the Red Army, accompanied by Soviet commissars of Polish origin, entered Poland. It broadcast appeals calling on Polish workers and peasants to seize properties of the bourgeois and landlords—slogans that had proven very effective in Russia. But the Poles of all classes rallied to defend newly won Polish sovereignty. In the battle for Warsaw, one of the decisive battles of modern history, they repulsed and scattered the Communist army. Lenin could not conceal his bitterness at this outcome."