Originally Posted by GUWonder
On the contrary, many more people on buses are killed by terrorists and small bombs this year and last than in planes in double the period.

Which is unresponsive to the point that when you blow up a bus you only get the people directly in the blast radius, but a relatively small explosion on a plane has a much larger impact.
Al Qaeda is looking to "improve" upon 9/11. A huge plot to bomb airliners accomplishes that. Small scale bus bombs don't.
Of course, if the terrorists had any clue about us, they'd do effective things like bomb the food court at a shopping mall the Friday after Thanksgiving, or the security line outside the Superbowl, or the line at the local DMV. But for now it's apparent that they're still fixated on air travel.