The Presidency of Barack Obama began at noon EST on January 20, 2009 when he became the 44th President of the United States. Obama was a United States Senator from Illinois at the time of his victory over Arizona Senator John McCain in the 2008 presidential election. Barack Obama is the first African-American president of the United States, as well as the first born in Hawaii.
His policy decisions have addressed a global financial crisis and have included changes in tax policies, legislation to reform the United States health care industry, foreign policy initiatives and the phasing out of detention of prisoners at the Guantanamo Bay detention camp in Cuba. He attended the G-20 London summit and later visited U.S. troops in Iraq. On the tour of various European countries following the G-20 summit, he announced in Prague that he intended to negotiate substantial reduction in the world's nuclear arsenals, en-route to their eventual extinction. In October 2009, Obama was awarded the Nobel Peace Prize for "his extraordinary efforts to strengthen international diplomacy and cooperation between peoples."