Susan Rice, currently the U.S. ambassador to the United Nations, will replace Tom Donilon as President Obama’s national security adviser. Obama nominated Samantha Power to replace Rice at the U.N. Read the full story by Scott Wilson and Colum Lynch here.

Both Rice and Power are known as advocates of military and humanitarian interventions in foreign countries:

The ideological shift signaled in the personnel choices highlights the central dilemma for Obama as he seeks to make a mark on the world at a time of austerity — and war weariness — at home. How ambitious Obama intends to be abroad at a time of stiff challenges on the domestic front has remained an open question months into his second term. . .

“They have deep moral commitments and they believe they are activists — both of them,” said Michael Doyle, a former assistant secretary general of the United Nations who is now a professor at Columbia University. “But they also have equally deep experience operating in the Washington bureaucracy — and know what’s possible, what’s not, what lever can be moved and which one can’t. That’s just as important.”

Scott Wilson

Still, the lack of attractive options for the Obama administration in Syria means that foreign policy is not likely to change, Max Fisher argues.

Power must still be confirmed by the Senate, but Rice’s new post does not require Senate confirmation. Obama had considered Rice for Secretary of State, but she withdrew to avoid a contest over her nomination in the Senate. Republican senators accused her of misleading the public following the attacks in Benghazi last year in which Islamist militants killed J. Christopher Stevens, the U.S. ambassador to Libya. Sen. John McCain (R-Ariz.), who was one of Rice’s most vocal opponents, tweeted today that he is willing to work with her in the future.

Correction: This article originally stated that President Obama nominated Susan Rice for Secretary of State. Rice withdrew from consideration before being nominated.