I remember a case a few years back involving a diplomat from the former Soviet republic of Georgia who was involved in a fatal drunk-driving accident in Washington, D.C. He fled the country under the protection of "diplomatic immunity," and the U.S. technically had no recourse in terms of prosecuting him.
I don't know what kind of pressure was put on the Georgian government, but eventually they not only sent him back for trial, but they also offered to send him back in 20 different FedEx packages.
And yet we won't. Can't offend our so called friends.
No pressure required ... our Egyptian allies will promptly extradite him.
[/sarcasm]
Think back: today's articles say that on Flight 93 the hijackers were heard saying "God is great."
Now, where have we heard THAT before?
Finding a prominent diplomat is one thing. Finding a single "ordinary" guy in the hot, dusty rabbit warren that is Cairo is quite another. Ordinary Egyptians have almost no credit card use, little legal / registered ownership of land, widespread corruption in the issuance of whatever few licences (driver's licence, etc) anyone might want to get, no ID checks in hotels ... there's no way to track someone down who doesn't want to be tracked. If he actually made it to Egypt (instead of being secretly detained along the way) that guy is GONE.