Answer :
Final answer:
The British waited to ensure the Zimmerman Telegram would prompt US entry into the war by revealing its threat and intensifying public opinion against Germany.
Explanation:
The British waited until they were sure the telegram would encourage the US to enter the war for several reasons. Firstly, the intercepted Zimmerman Telegram contained a direct threat on American soil, increasing public opinion against Germany. Secondly, the British intercepted and shared the decrypted message with the US public, intensifying anti-German sentiments and pushing for US intervention in the war.
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