Mattis says a North Korean missile strike on the U.S. would mean war.
“If they fire at the United States, it could escalate into war very quickly,” Mattis said.
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North Korea has said it is considering a plan to launch four ballistic missiles to land in the sea just short of Guam.
Asked how the U.S. would respond, Mattis initially declined to say.
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When pressed, he said that if U.S. radars and other detection and tracking systems determine that a missile was going to fall into the sea, short of Guam, then the matter would be taken to President Donald Trump for a decision on how to respond.