Final answer:
The Japanese were able to surprise the US at Pearl Harbor by using aircraft carriers to approach Hawaii unnoticed.
Step-by-step explanation:
The Japanese were able to surprise the US at Pearl Harbor by using their aircraft carriers to approach Hawaii unnoticed. Prior to the attack, the Japanese had stationed their carriers far enough away from Hawaii that they would not be detected by radar. This allowed them to launch their planes and carry out the surprise attack on Pearl Harbor.
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