1. Intercepted Message: In January 1917, British intelligence intercepted a coded telegram sent by German Foreign Minister Arthur Zimmermann to the German ambassador in Mexico. The message proposed an alliance between Germany and Mexico if the United States entered World War I on the side of the Allies. Germany promised to provide financial support and help Mexico regain territories lost to the United States in the Mexican-American War (1846-1848).
2. Publication: The British shared the decoded telegram with the United States government. President Woodrow Wilson decided to release the telegram to the public on March 1, 1917. Publication of the telegram infuriated the American public and further soured relations with Germany.
3. Outrage in the US: The telegram caused outrage in the United States. Americans were offended by the suggestion that Germany would attempt to form an alliance with Mexico against the United States. Many saw it as a violation of the Monroe Doctrine, which declared the United States' sphere of influence in the Americas.
4. Diplomatic Efforts Fail: Following the release of the telegram, the United States and Germany engaged in diplomatic negotiations. However, these efforts failed as Germany refused to renounce unrestricted submarine warfare, which resulted in the sinking of American merchant ships and loss of American lives.
5. Impact on US Public Opinion: The Zimmermann Telegram shifted public opinion in the United States further towards supporting entry into World War I. Many Americans felt that Germany's actions demonstrated its disregard for international law and posed a threat to American security.
6. Declaration of War: On April 6, 1917, President Woodrow Wilson asked Congress to declare war on Germany. The United States officially joined the Allied forces on the Western Front.
In summary, the Zimmermann Telegram's significance lies in its role as a catalyst that fueled anger and distrust among Americans, influencing public opinion, and ultimately leading the United States into World War I on the side of the Allies.