US - Why the Democrats fear The Path to 9/11

Here's one reason from the Washington Post.

On the front lines in Pakistan and Central Asia, working-level CIA officers felt they had a rare, urgent sense of the menace bin Laden posed before Sept. 11. Yet a number of controversial proposals to attack bin Laden were turned down by superiors at Langley or the White House, who feared the plans were poorly developed, wouldn't work or would embroil the United States in Afghanistan's then-obscure civil war. At other times, plans to track or attack bin Laden were delayed or watered down after stalemated debates inside Clinton's national security cabinet.

At Langley, CIA officers sometimes saw the Clinton cabinet as overly cautious, obsessed with legalities and unwilling to take political risks in Afghanistan by arming bin Laden's Afghan enemies and directly confronting the radical Taliban Islamic militia. But at the Clinton White House, senior policymakers and counterterrorism analysts sometimes saw the CIA's efforts in Afghanistan as timid, naïve, self-protecting and ineffective.

Wile Clinton and the CIA fumbled away, bin Laden was making bigger plans.

Their reports described over and over bin Laden's specific, open threats to inflict mass casualties against Americans. They could not understand why no one else seemed to take the threat as seriously as they did. They pleaded with colleagues that bin Laden was not like the old leftist, theatrical terrorists of the 1970s and 1980s who wanted, in terrorism expert Brian Jenkins's famous maxim, "a lot of people watching but not a lot of people dead." Bin Laden wanted many American civilians to die, they warned. They could be dismissive of colleagues who did not share their sense of urgency.

While bin Laden was making repeated and open threats of mass casualties against Americans, back at the White House Clinton shared a "sense of urgency" with Monica - and a cigar we'er told.