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John Bolton in, H.R. McMaster out in latest White House shakeup

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President Trump announced in a tweet that he is replacing Army Lt. Gen. H.R. McMaster as national security adviser with John Bolton, the former U.S. ambassador to the United Nations. White House officials say Trump wanted to fill out his national security team before his upcoming sit-down with North Korean dictator Kim Jong Un. NBC national correspondent Peter Alexander reports for TODAY.