Zimmerman telegram was a turning point in many U.S. citizens' attitude about entering the war because its contains that Germany would cede United States territory to Mexico if Mexico cooperated with the German military..

<h3>What was the Zimmerman telegram?</h3>

It was an transmitted message that contains a secret diplomatic writing which was intended by Germany to form an alliance with Mexico.

Prior to the war, the U.S. States intended to fight against the Germans during the first world War and the Germans intended to form an alliance with Mexico if the US engaged against them.

Hence, because the telegram message contains an agreement made by Germany to cede US territories to Mexico if they cooperate, it became the turning point in which many U.S. citizens' attitude about entering the war began.