What did Russia do to encourage U.S participation in world War 1

The United States joined World War I mainly because of the sinking of the Lusitania, a neutral passenger ship. Another reason for joining the war was the Zimmerman Telegram that was intercepted by the United States. In it Germany was making an alliance with Mexico in order to attack the U.S. Russia further pushed the U.S. to join after signing a peace treaty with Germany and leaving the Allies.
Updated on Wednesday, February 01 2012 at 05:08PM EST
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