thomas e. "tom" donilon (born may 14, 1955) is a former united states government official. he was the national security advisor in the obama administration. he has had a career as a u.s. political advisor, government official and lawyer. previously, he served together with diplomat wendy sherman as agency review team lead for the state department in the obama transition, and as deputy to national security advisor james jones early in the obama administration. donilon replaced jones as national security advisor on october 8, 2010. donilon announced his resignation as national security adviser on 5th june 2013. susan rice was his successor.