I first want to comment on what Professor Salter just said.
There is no intelligence involved in the trusted traveller program in Israel--none whatsoever. We do give trusted travellers to foreigners; we don't know anything about them. But I can tell you this about the 9/11 people: we would have caught them one by one, because they had something to hide, and we find out if you have something to hide. This is a very good system, and I do hope that somebody will take note of it.
For the perimeter security, I don't want to scare you guys, but I can take a pickup truck today, fill it with 500 kilos of explosives, drive to the front door of the terminal at Pearson, and blow it up. You will have an aviation disaster almost as big as it was in Europe with the ash. You don't even mind that all this glass that is built in the airport is not blastproof. People won't be killed by the blast. They will be killed by the glass.
You do have to know who is entering your airport. If you have a suspicious vehicle, you have to stop it. You have to stop it at such a distance that if, God forbid, it is a suicide bomber, then you can mitigate it before it creates any harm.
I can go on and on. You know the security lines you have at the airports? It's the biggest threat to aviation ever. You do not want many people to stand in one place. You want them to flow. If you stop the flow and have them wait three hours in line for a 10-second security, this is not a security measure. This is a security risk.