Trapped in al-Qaida's Tora Bora cave network two months after the attacks of Sept. 11, 2001, Osama bin Laden seemed prepared to die. Instead, he was allowed to escape: The United States never fielded a serious ground effort to stop him, instead pointlessly trying to bomb him from the sky and handing out cash to Afghan warlords who had no intention of capturing him. The disaster flowed from one bad idea: that the United States could win in Afghanistan without a 'big footprint,' using locals who wouldn't trigger the renowned Afghan hostility to foreign invaders. Not to mention that deploying a small contingent of special forces armed with cash would prove Defense Secretary Donald Rumsfeld's ideological point about the need to transform the U.S. armed services from a lumbering Cold War conventional force into a leaner, meaner, high-tech military capable of lightning strikes. Rumsfeld may have been right about the need for transformation. But Tora Bora was a case study not in innovation but in the arrogance of a superpower that made bad decisions in the face of overwhelming evidence that they wouldn't work. Seen from the ground, and despite the assurances of Pentagon spokesmen in Washington that bin Laden was cornered, the evidence slammed us in the face: rows of massive peaks in the White Mountains connecting Afghanistan and Pakistan. With no American troops to cover those mountains and only handfuls of Afghan militiamen rattling up the Tora Bora road, nearly barefoot in the snow and clinging to pickup trucks and worn Kalashnikovs, it was inconceivable that bin Laden was surrounded. The 100 or so international journalists gathered there (outnumbering the U.S. forces) saw little more than sporadic gunfire, surreal warlord news conferences (We've killed Zawahiri! Al-Qaida is surrendering!), a few rusted tanks from the Soviet war and the spectacle of B-52 bombing runs. After the battle, I returned there to find out what had really happened. Local Afghans told me in early 2002 the same thing that a Senate Foreign Relations Committee investigation has recently concluded: Corrupt warlords allowed bin Laden to escape while the special forces pleaded with the Pentagon to let them get in the fight. It was probably around the night of Dec. 13, 2001, that a tall man known as the sheik gathered his men, drank tea and then fled toward Pakistan. For years, the failure at Tora Bora would spark Washington bickering; the accusation that Rumsfeld & Co. 'outsourced' the war was a centerpiece of Sen. John Kerry's 2004 presidential bid. But it was much more than a botched military operation. Given the lives since lost and the effort since expended in the hunt for bin Laden and the war against al-Qaida, we are still suffering the consequences of the decision not to fight at Tora Bora. Susan B. Glasser, executive editor of Foreign Policy magazine, covered the battle of Tora Bora for The Washington Post. 