Washington (CNN) -- Finding al Qaeda leader Osama bin Laden and rolling back a resurgent Taliban are necessary steps toward winning the war in Afghanistan, the top U.S. commander there told a Senate committee Tuesday. Bin Laden remains at large more than eight years after the September 11, 2001, attacks on New York and Washington that triggered the Afghan war, and is widely believed to be hiding along the rugged border between Afghanistan and Pakistan. Gen. Stanley McChrystal, the commander of U.S. forces in Afghanistan, said the world's most wanted terrorist is "an iconic figure" whose survival "emboldens al Qaeda as a franchising organization across the world."
@highlight
NEW: "I don't think we can finally defeat al Qaeda" without getting bin Laden, McChrystal says
@highlight
NEW: General, U.S. ambassador testify before House and Senate armed services committees
@highlight
McChrystal: Perceptions of Afghan people and insurgency will be critical to success
@highlight
McChrystal: "I don't view July 2011 as a deadline."
One advantage U.S. troops have is that the Taliban -- which ruled most of Afghanistan before the 9/11 attacks -- remain largely unpopular among @placeholder and draw support only through the threat of violence.