Explanation: In WW1, Germany specifically allowed the Communist leader Lenin to return to Russia, which had recently overthrown the Tsar. They did so, despite being an enemy of Communists, in the hopes that Lenin's return would sow discord and undermine Russia. They were half-right - the Bolshevik resurgence contributed to the peace treaty signed by Russia in WW1, but the Bolshevik insistence on maintaining the Russian Empire under a red facade came with later consequences that would be... less appealing to Germany's national interests.
