Final answer:
The Zimmermann Telegram was a German offer to Mexico to recover lost land in exchange for their support in World War I.
Step-by-step explanation:
The Zimmermann Telegram was a German offer to help Mexico recover land lost in the Mexican-American War if Mexico would side with Germany in World War I. This diplomatic communication was intercepted and decoded by the British intelligence, who then shared it with the United States. The Zimmermann Telegram played a significant role in pushing the United States towards joining World War I on the side of the Allies.
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