 Complete the following phrase:  In 1933, the Roosevelt Administration extended diplomatic recognition to the Soviet Union and Henderson was assigned to Russia to help reopen the U.S. Embassy in Moscow. Aiding him in this task were fellow junior officers George F. Ken and Charles Bohlen, who along with Henderson would later be considered the Departments top Soviet specialists. In 1935, the Kremlin broke its pledge to not to interfere in U. S. domestic politics. In response, Ambassador Bullitt returned to Washington in disgust, leaving Henderson for a time as chargé daffaires in Moscow. As chargé, Henderson warned Washington that the Soviet Union was likely to cooperate with Nazi Germany. Four years later, Moscow signed the 