The Man Behind Obama's Foreign Policy It is Tom Donilon, James Mann wrote in a recent FP profile, "who, working directly with Obama throughout each day, helps the president decide whether to intervene in Syria, what to do about Chinese cyberhacking, and how to deal with Iran's and North Korea's nuclear programs." When it comes to formulating U.S. foreign policy, Vice President Joe Biden once told the New York Times, Donilon is "the most important person in the mix." Now that person is leaving, with U.N. ambassador Susan Rice slated to take over as Barack Obama's national security advisor. Here's a look back at some of the images that have marked Donilon's five influential years in the White House. Above, Obama shares a laugh in the Oval Office on Oct. 8, 2010 with Donilon, left, and then National Security Advisor James L. Jones, right, before the announcement that Jones would leave his post and be succeeded by Donilon. Flickr/The White House Obama talks with Donilon in the hallway outside his hotel suite in Santiago, Chile on March 21, 2011. Obama gives the final authorization for the U.S. military to intervene in Libya during a conference call with Donilon and then-Chief of Staff Bill Daley in Brazil on March 19, 2011. Flickr/White House Donilon answers questions during a visit to the Economic Club of Washington on Sept. 16, 2011, in Washington, D.C. Donilon participated in a question-and-answer discussion on national security issues facing the United States. Win McNamee/Getty Images Obama walks through the Rose Garden of the White House with Donilon on April 14, 2011. Then-Secretary of State Hillary Clinton and Donilon attend a meeting between Obama and India's Prime Minister Manmohan Singh on the sidelines of the Association of Southeast Asian Nations (ASEAN) and East Asia summits in Nusa Dua on Indonesia's resort island of Bali on Nov. 18, 2011. Obama speaks with Donilon and U.N. Ambassador Susan Rice during a high-level meeting on Libya at the United Nations in New York on Sept. Donilon speaks during a daily press briefing at the White House on May 17, 2012. Donilon briefed reporters on an upcoming G-8 summit at Camp David and a NATO summit in Chicago. Clinton, then-Defense Secretary Leon Panetta, and Donilon listen as Obama and NATO Secretary-General Anders Fogh Rasmussen deliver remarks during the NATO Summit in Chicago on May 20, 2012. Obama has lunch with Donilon and Abu Dhabi Crown Prince Mohammed bin Zayed Al Nahyan of the United Arab Emirates in the Oval Office Private Dining Room on June 27, 2012. Obama talks with Donilon before a phone call with President Mohamed Morsy of Egypt aboard Air Force One during a flight from Phnom Penh, Cambodia, to Washington, D.C. on Nov. 20, 2012. Donilon and Gen, Fan Changlong, vice chairman of China's Central Military Commission, talk during their meeting at the Bayi Building, headquarters of the Chinese Defense Ministry, on May 28, 2013 in Beijing, China. Alexander F. Yuan-Pool/Getty Images John Kerry, then a Massachusetts senator, shakes hands with Donilon outside the West Wing of the White House on Dec. 28, 2012, shortly after Obama nominated Kerry to be the next secretary of state. Mandel Ngan/AFP/Getty Images The now-iconic image of Obama's national security team monitoring the Osama bin Laden raid on May 1, 2011, at the White House. Donilon is standing, arms folded, behind the black chair.