I truly think that if people are worrying about the proximity of DCA to the Pentagon and other locations in the city, they should be thinking about accidents, not terrorists. Because other than the potential for accidental crashes, I still don't understand how DCA is considered any less safe than IAD and BWI.

First off, I don't think a plane can be hijacked out of DCA in time to crash into the city. You'd have about 10 seconds (while ascending) to seize control of the cockpit. So then the worry is that the hijackers seize control while it's landing. Well, guess what, IAD and BWI are still about 3-5 minutes flying time from the city center. I really am dubious about the ability to scramble fighters in time to intercept a plane hijacked that was heading toward one of those two airports originally. (And this isn't to mention the fact that I think the terrorists will try something different for their next plan anyway.)

Shutting down DCA is more than just a symbolic victory. It is also an economic victory. DCA employs 10,000 workers directly, and brings air traffic into a region that employs countless more rental car employees, cab drivers, restaurant owners, hotel owners, etc. These associated businesses account for estimated 70,000 other employees. Shutting down the airport for two weeks has cost the economy an estimated $192 million. A 1998 study found that the airport pumps $5.3 billion dollars into the local economy each year.

And it's not just a symbolic and economic victory, but a transportation-related one as well. Where are all these travellers going to go? Some of the air traffic can be handled by BWI or IAD, but obviously not all of it. When air traffic returns to normal levels the airports will be saturated with travellers.

If I thought the airport truly contributed a significant threat my opinion on the matter would be different. The thing is, for reasons outlined above, I just don't see it. I can understand instigating certain safety measures, such as requiring only southward bound (i.e., away from DC proper) takeoffs. That in and of itself would limit the number and size of flights that could utilize DCA. But I see that more as a precaution against accidents than terrorist activities.