People gather on the National Mall during the inaugural ceremony for Barack Obama as 44th US president at the US Capitol in Washington on January 20, 2009. Two million people erupted in joyous celebration, cheering and waving a sea of flags as Barack Obama took the oath of office as the first black president of the United States.   AFP PHOTO/Jewel SAMAD (Photo credit should read JEWEL SAMAD/AFP/Getty Images)