WASHINGTON — Shaking up his national security team, President Barack Obama tapped diplomat Susan Rice as his national security adviser, defying Republicans who have vigorously criticized her faulty explanation about the attack on Americans in Benghazi, Libya.

“Susan is the consummate public servant — a patriot who puts her country first,” Obama said while announcing Rice’s appointment today during a Rose Garden ceremony.

Rice will take over the top national security post from Tom Donilon, who is resigning after four years in the White House. Obama lauded the 58-year-old Donilon for having “shaped every single national security policy of my presidency,” including the renewed U.S. focus on ties with Asia.

Obama also announced the nomination of former aide Samantha Power to replace Rice as U.S. ambassador to the United Nations. Power is a human rights advocate and expert on genocide.

For Rice — a longtime Obama ally and close confidante of the president — the appointment is a bit of redemption after she was forced to withdraw from consideration as Obama’s second-term Secretary of State amid criticism of her handling of the Benghazi attacks. Rice said at the time that she did not want her confirmation hearing to become a distraction for the White House. The national security post does not require Senate confirmation.