Afghan presidential candidates Abdullah Abdullah (L) and Ashraf Ghani Ahmadzai shake hands after signing a power-sharing agreement at the Presidential Palace in  Kabul on September 21, 2014. Afghanistan's two rival presidential candidates signed a power-sharing deal on September 21, ending a prolonged stand-off over disputed election results at a pivotal moment in the war-weary nation's history. AFP PHOTO/Wakil Kohsar        (Photo credit should read WAKIL KOHSAR/AFP via Getty Images)