WASHINGTON — Defying Republican critics, President Barack Obama named outspoken diplomat Susan Rice as his national security adviser Wednesday, giving her a larger voice in U.S. foreign policy despite accusations that she misled the nation in the aftermath of the deadly attack on Americans in Benghazi, Libya.

The appointment, along with the nomination of human rights advocate Samantha Power to replace Rice as U.S. ambassador to the United Nations, signals a shift by Obama toward advisers who favor more robust American intervention overseas for humanitarian purposes. But it's unclear whether that philosophy will alter the president's policies in Syria, where he has resisted pressure to use U.S. military force to stem that country's civil war.

Rice's appointment provides a measure of redemption after the contentious Benghazi investigations forced her from consideration as Obama's second-term secretary of state. The president, who vigorously defended Rice from the GOP criticism at the time, lauded his close friend Wednesday as a "patriot who puts her country first."

"Susan is a fierce champion for justice and human decency. But she's also mindful that we have to exercise our power wisely and deliberately," Obama said in a White House Rose Garden ceremony.

The 48-year-old Rice takes the influential national security post in the president's inner circle from Tom Donilon, who is stepping down in July after more than four years in the Obama White House. The president credited Donilon with having "shaped every single national security policy of my presidency," including the renewed U.S. focus on the Asia-Pacific region and the tricky American relationship with Russia.

Wednesday's announcements came as Obama seeks to regroup from three controversies that have emboldened Republicans and threatened to overshadow his agenda: the Internal Revenue Service's targeting of conservative political groups, the Justice Department's seizure of phone records of Associated Press journalists and the resurgent investigation into the deaths of four Americans in Benghazi, including Ambassador Christopher Stevens.

Rice became entangled in the Benghazi case after asserting in television interviews that the September attack was probably spontaneous, a statement that was later proven false. While Rice said she was relying on talking points crafted by the administration, she became a target for Republicans accusing the White House of trying to cover up a terror attack during the presidential election.

But because Rice's new job does not require Senate confirmation, some of the GOP lawmakers who doled out the most aggressive attacks appeared resigned to her promotion through the ranks of Obama's national security team.

Arizona Sen. John McCain, one of Rice's harshest critics, wrote on Twitter Wednesday that he disagreed with her appointment but would "make every effort" to work with her on important matters.

The toughest criticism of Rice Wednesday came from Sen. Rand Paul, R-Ky., a member of the Senate Foreign Relations Committee who tangled with former Secretary of State Hillary Rodham Clinton over Benghazi at a hearing earlier this year. In a series of tweets, Paul said he questioned "the president's judgment in promoting someone who was complicit in misleading the American public on the Benghazi attacks."

In an ironic twist for her Republican adversaries, Rice may end up wielding more authority in U.S. foreign policy from within the White House than she would have as head of the State Department. Under Obama, the White House, not the State Department or other agencies, has become the power center for the administration foreign policy decision-making.

Standing alongside Obama in the Rose Garden, Rice said she looked forward to working with lawmakers from both parties "to protect the United States, advance our global leadership and promote the values Americans hold dear."

Rice first started working for Obama during his 2008 presidential campaign and already has a close friendship with the president as well as the trust of many of his advisers. She's been a strong advocate at the U.N. for stricter sanctions against Iran and North Korea, and also pushed for the U.S. and allies to use military force to help Libyan rebels oust longtime leader Moammar Gadhafi in 2011.

Rice previously served in various national security positions in President Bill Clinton's administration, including key roles on peacekeeping and African affairs. Her world view is said to have been shaped by Clinton's decision to not intervene in the Rwandan genocide, a move Rice said later deeply affected her.

Power, a human rights advocate and genocide expert, was among the fiercest critics of Clinton officials, including Rice, who kept the U.S. out of Rwanda.

A former journalist, Power won the 2003 Pulitzer Prize in general nonfiction for her book "A Problem From Hell: America and the Age of Genocide," which examined U.S. foreign policy toward genocide in the 20th century.

Power served as an adviser to Obama's 2008 presidential campaign, but resigned after calling then-rival Hillary Clinton a "monster." She later joined Obama's national security staff at the White House, overseeing the human rights portfolio.

Despite their reputations as interventionists on humanitarian grounds, neither Rice nor Power has staked out a public position on Syria that differs from the president's. And the White House sought to tamp down the notion that their new roles signaled a policy shift, particularly in Syria.

"Ultimately it is the president of the United States who assesses the views of his foreign policy team when there are issues to be debated and then makes the decision," press secretary Jay Carney said. "The president's policy on Syria will be the president's policy as it is today."

The shake-up at the top echelons of Obama's team comes just as he starts tackling a heavy foreign policy agenda. He's scheduled to hold an unusual summit in California with Chinese President Xi Jinping starting Friday, then travel to Europe and Africa later this month.

Donilon, who helped orchestrate the China summit, will stay in his job until early July. The 58-year-old has been a constant presence on Obama's national security team since the president's first day in the White House, wielding significant influence while maintaining a low-key style.

Donilon has overseen a foreign policy agenda that has put increased emphasis on the U.S. relationship with Asia. He's also played a key role in the administration's counterterrorism strategy, including the raid that led to the death of Osama bin Laden, and in managing the complex U.S. ties with Russia.

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Associated Press writer Donna Cassata contributed to this report.

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Follow Julie Pace at http://twitter.com/jpaceDC

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