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While President Donald Trump rattles sabers on Twitter and slams "Rocket Man" Kim Jong Un, there is also a perceptible hardening of tone among senior officials.
**This image is for use with this specific article only.**

While President Donald Trump rattles sabers on Twitter and slams "Rocket Man" Kim Jong Un, there is also a perceptible hardening of tone among senior officials.

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    White House defends Trump's nuclear taunting

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White House defends Trump's nuclear taunting

President Donald Trump's escalated statements against North Korea have revived questions in Washington about the President's authority to approve the use of nuclear weapons. CNN's Barbara Starr reports.

White House defends Trump's nuclear taunting

President Donald Trump's escalated statements against North Korea have revived questions in Washington about the President's authority to approve the use of nuclear weapons. CNN's Barbara Starr reports.