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Then when the war in the Pacific started in December 1941, it became necessary for the US military (at the request of the British) to assume responsibility for the defense of New Zealand & Australia. The Australian military was in a similar situation. American troops were also in New Zealand for training, prior to combat.
The 2nd New Zealand Division under the command of General Freyberg was sent to the Italian front where they participated in the attack on Monte Cassino. General Freyberg was the local commander who requested the Allies bomb the Abbey of Monte Cassino so they could capture that massive hill. This request was forwarded up through the command and approved by the 15th Army Group. Some say this was a political decision that was made in order to appease the New Zealand troops.