It's a near certainty that remaining Al-Queda terrorists are in the US and other Western countries and are waiting for the signal for launching a second wave of terrorist attacks. That signal, of course, will be the start of the US-UK led air strikes on the Taliban/OBL.

By delaying the air strikes a week or two, we are also delaying the terrorist counter-attack, and giving ourselves some more time to uncover hidden Al-Queda operatives (if we're lucky a few of them may get nervous and give themselves away), prepare for counter-attack, and most importantly, we are dictating that this war will be waged on our terms, at a tempo and intensity of our choosing, not the terrorists.