If September 11 comes and goes, and nothing happens (nothing serious in America that is...not a car bomb at some obscure embassy in Africa), I think we will have learned something important:

Al Quaeda may have pretty much shot its wad. At the height of their powers and funding, they managed to mount one attack that got through a loophole in our airline security and hijacking protocols, and accidentally found a structural weak spot in a couple of skyscrapers (I think the terrorists had no real idea the WTC would collapse after the impact).

Okay, the argument can be made that they will pick some obscure date to try something just to catch us off guard, but it won't have the same impact and they know it.

I was kind of surprised that the Fourth of July went by without incident. If September 11 does too, well, maybe they just don't have what it takes any more to top their first big triumph. We'll see.

P.S. my instinct says they will try poison or something quiet for the next attack. Comments?