US President Barack Obama has vowed to deny al-Qaeda safe heaven and reverse Taliban's momentum in Afghanistan. Obama who made a surprise visit to Kabul and met President Hamid Karzai yesterday said, the mission of America is to disrupt and dismantle, defeat and destroy al-Qaeda and its extremist allies. Addressing the US soldiers at the Bagram airfield, the US President reiterated his country's support to strengthen the capacity of Afghan forces and the Afghan government so that they could take responsibility and gain confidence of their own people. He said, Al-Qaeda and their extremist allies were not only a threat to the people of Afghanistan and America, but also a threat to the people all around the world. Recollecting 9/11 attack, Obama said this was the region where the perpetrators of the crime, al-Qaeda, still had their leadership. Apart from the military effort to take the fight to the Taliban, Obama said his Afghan policy included civilian effort which aimed to improve daily lives of Afghans, combat corruption, and a partnership with Pakistan and its people. Across the border, the US President said Pakistan has mounted a major offencive against terrorism in its territory. He added that the United States would continue to pursue the Taliban and al-Qaeda as it was required to ensure the safety of American families back home.