The message sent by Arthur Zimmermann was significant due to its strategic implications, urgency, and the proposed alliance with Mexico against the United States during World War I.
The importance of the message sent by Arthur Zimmermann can be inferred from the route it took and the strategic implications it held.
The fact that the message was sent via a U-boat to ensure its delivery to Washington suggests its significance and the urgency Zimmermann attached to it.
Furthermore, the content of the message proposing an alliance with Mexico against the United States during World War I highlights the high stakes involved and the impact it could have had on international relations.
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