Updated

The Clinton and Bush administrations secretly considered but ultimately rejected a range of military actions against Usama bin Laden (search) and his Al Qaeda (search) network prior to Sept. 11, 2001.

A preliminary report by the Sept. 11 commission found that while the U.S. government pursued diplomacy and sought a better military plan, bin Laden and other Al Qaeda leaders eluded capture. A recurring theme in the report is that U.S. leaders believed they lacked "actionable intelligence" — timely and reliable information — on bin Laden's whereabouts.

Here is a look at some of the options considered during that period and why none achieved its aim:

— Following the Aug. 20, 1998, U.S. cruise missiles strikes at a terrorist training camp in Afghanistan — which failed in their aim of killing bin Laden — the Pentagon prepared a plan, code-named Operation Infinite Resolve, for follow-up strikes. But within days, senior Pentagon civilian officials determined that the targets were not promising.

— Simultaneously, the White House's lead official on counterterrorism, Richard Clarke (search), prepared a political-military plan envisioning a campaign of small regular strikes at Al Qaeda targets. The question debated within the administration was whether it was worth using very expensive missiles to take out what Gen. Henry Shelton, chairman of the Joint Chiefs of Staff, called "jungle gym" training camps. Defense Secretary William Cohen (search) also opposed the plan, saying the camps were primitive facilities with "rope ladders." Others in the administration said small strikes might be counterproductive by raising bin Laden's stature in the Islamic world.

— In December 1998, Shelton ordered planning for the use of commandos to capture Al Qaeda leaders inside Afghanistan and transport them from the city of Kandahar. Plans refined through 1999 added options, including the possible use of strike aircraft. Shelton warned that if such an operation failed, it could be an international embarrassment for the United States. Ultimately, the plan was dropped for lack of timely and reliable intelligence on bin Laden's whereabouts.

— In February 1999, the CIA received reports that bin Laden was at a desert camp in Afghanistan adjacent to a larger hunting camp in Helmand province. The location of the larger camp was confirmed on Feb. 9 but the location of bin Laden's quarters could not be determined precisely. Preparations were made for a strike against the larger camp, but it was not launched. CIA officials said policy-makers were concerned that an attack might kill innocents.

— In May 1999, a CIA source provided "very detailed" reports on bin Laden's whereabouts over the course of five days in the vicinity of Kandahar, Afghanistan. No strike was launched because the intelligence information was based on a single uncorroborated source and there was a risk that untargeted individuals would be hit.

— On another occasion in July 1999, intelligence placed bin Laden in Ghazni, Afghanistan. The Sept. 11 commission report provided no other details on that situation and said it is still investigating the circumstances.

"There were no occasions after July 1999 when cruise missiles were actively readied for a possible strike against bin Laden," the report said. "The challenge of providing actionable intelligence could not be overcome before 9/11."