During World War I, the U.S. had been among the nations that had sent troops to Russia after the Russian Revolution. Afterwards, President Wilson refused to provide diplomatic recognition to Russia, which was led by a Communist government following the October Revolution. Commerce Secretary Hoover, with considerable experience of Russian affairs, took the lead on Russian policy. He supported aid to and trade with Russia, fearing U.S. companies would be frozen out of the Soviet market. When famine struck Russia in 1921, Hoover had the American Relief Administration, which he had headed, negotiate with the Russians to provide aid. According to historian George Herring, the American relief effort may have saved as many as 10 million people from starvation. U.S. businessman such as Armand Hammer invested in the Russian economy, but many of these investments failed due to various Russian restrictions on trade and commerce. Russian and (after the 1922 establishment of the Soviet Union) Soviet leaders hoped that these economic and humanitarian connections would lead to recognition of their government, but Communism's extreme unpopularity in the U.S. precluded this possibility.