I have heard on the news that Barbara Olson, wife of Bush administration Solicitor General Ted Olson, was on the plane that hit the Pentagon. Apparently she got a call out before the impact, and said the hijackers were using "knives and cardboard cutters," confirming the use of edged weapons instead of guns or bombs.

At first glance, it would seem that the dozens of passengers and flight crews should have been able to overwhelm a few hijackers armed only with knives. I think I know why this didn't happen.

Up until now, most hijackings have been relatively benign as far as most of the airplane passengers, and even the crew, have been concerned. Although there have been some unpleasant exceptions, the general scenario has involved planes parked on runways, negotiations, threats, and uncomfortable hours without air conditioning. As a passenger, your best bet was to lay low, don't attract attention, and do what you're told. Eventually, it was likely the passengers would be released.

It's very likely that not even the flight crew (much less the passengers) were told what the terrorists were going to do with the planes until it was too late.

This won't be true in the future. You can bet any hijackings that take place from now on may meet with considerably more resistance from flight crews and passengers. It's possible that what happened with the plane that crashed in Pennsylvania was that somehow the crew and passengers discovered the terrorists' suicide intentions and fought like cornered rats.