Obama makes surprise visit to Afghanistan KABUL - President Obama made an unannounced visit to Afghanistan on Tuesday, landing on the one-year anniversary of the attack that killed Osama bin Laden and during a pivotal moment in U.S-Afghan relations, as the two countries look to define their military and economic ties beyond 2014. Obama landed at Bagram air base north of Kabul at 10:20 p.m. local time and boarded a helicopter shortly afterward for a flight into the capital. He arrived at the Afghan presidential palace just after 11 p.m. local time for a meeting with President Hamid Karzai. He was expected to sign a strategic partnership agreement with Karzai, then address the American people on live television at 7:30 p.m. Tuesday Washington time. Since Obama's last visit to Afghanistan in December 2010, the president's 33,000-troop surge has begun to ebb, and public support for the war has faded. More than 10 years into the fight against al-Qaeda and the Taliban, Afghan leaders have pleaded with Obama for an enduring American footprint while also demanding more control over military operations within the country's borders. For his part, Obama has been careful to underscore the effectiveness of the bin Laden raid in crippling al-Qaeda's reach while continuing to emphasize the need for American troops to root out the Taliban and ensure security in Afghanistan. Bin Laden was killed by helicopter-borne U.S. Navy SEALs who flew into Pakistan from a base in Afghanistan and raided the al-Qaeda leader's house in Abbottabad, a garrison town north of the Pakistani capital. Karzai has long requested reassurance from Obama that American support would not wane after 2014, when the last NATO combat troops are due to leave the country. With the completion of a draft strategic partnership agreement last month - finished after more than a year of wrangling - Afghans are now eager for a public articulation of that long-term U.S. commitment. Obama's visit is aimed in part at quelling Afghan fears of an abrupt American departure, despite the lack of concrete promises made in the partnership agreement. Still, the signing of the agreement marks not just a U.S. pledge over the next decade, but also a detente after some of the tensest months in U.S.-Afghan relations. Since February, American service members have inadvertently burned Korans at a U.S. military base, Army Staff Sgt. Robert Bales allegedly murdered 17 civilians in Kandahar, and at least 18 NATO troops have been slain by their Afghan counterparts.