Final answer:
Britain highlighted violations of American neutral rights, Germany's actions pushed the U.S. towards war, and Russia's revolution influenced American perception.
Step-by-step explanation:
15. Britain: Britain encouraged U.S. participation in the war by highlighting the violation of American neutral rights, such as the sinking of the Lusitania by a German submarine. They also used propaganda to portray Germany as a threat to democracy.
16. Germany: Germany attempted to discourage U.S. participation in the war by issuing the Sussex Pledge, promising to limit submarine warfare. However, their resumption of unrestricted submarine warfare and the Zimmerman Telegram, which proposed an alliance between Germany and Mexico against the U.S., ultimately pushed the U.S. towards war.
17. Russia: Russia's involvement in the war before the U.S. entry served as a factor that pushed the U.S. towards participation. Russia's revolution in 1917, which led to the overthrow of the Tsarist government, created a more favorable perception of Russia in the eyes of the American public.
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