Defense Secretary James Mattis on what keeps him up at night: 'Nothing. I keep other people awake'

AP

Defense Secretary James Mattis pulled out a casual punchline Sunday when an interviewer asked what threats around the world keep him up at night.

"What keeps you awake at night?" CBS host John Dickerson asked Mattis during an interview on "Face The Nation."

"Nothing. I keep other people awake at night," Mattis responded, almost instantly.

Mattis' appearance on "Face The Nation" came after the conclusion President Donald Trump's first trip abroad. The defense secretary discussed the battle against ISIS in the wake of the suicide bombing in Manchester, England, as well as the threat posed by North Korea and Trump's heavily criticized speech at NATO's headquarters.

Watch his comments below:

And check out the full interview here >>

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