President Obama will announce today that National Security Adviser Tom Donilon is resigning and will be replaced by UN Ambassador Susan Rice.
The president will also announce that he is nominating Samantha Power to succeed Rice as the U.S. ambassador to the United Nations.
The president has long-supported Rice and his decision to nominate her as one of his top advisers is a clear rejection of Republican criticism of her response to the deadly attacks on the American outpost in Benghazi.
The position of national security adviser is not subject to Senate confirmation.
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