All kinds of organizations, either from malice or stupidity, have taken advantage of 9/11 to further their own ends. The police have been the worst. Photographers and cops used to get along pretty well, but since the Rodney King beating in LA, I think cops have more and more viewed photographers as threats to their jobs, and have taken advantage of 9/11 security concerns to attack photographers' rights. Although the situation in Canada and the UK is somewhat different, in the US we have a positive right to take photographs in public places. And guess what -- in the US, if you can see the building from a public place, like a sidewalk, you can take a picture of it and if you call it art, you can sell the picture; any supposed copyright of a building is worthless. (You can be restricted from taking photos on private property, just as you can be restricted from even entering private property.)
There's also a curious kind of provincialism at work. The county seat where I live is in Stillwater, Mn. The county courthouse closed one set of entrances to the public because of "security concerns." Is the county courthouse at Stillwater, Mn., going to be attacked by international terrorists? One would hesitate to think so...but for the people in that courthouse, it makes perfect sense. What courthouse (to them) could possibly be more important? Though there may have been other issues, as well...when they closed the entrances to the public, they left them open to employees. Now the most convenient parking lot and entrances are employee-only. As though an international terrorist, intent on reducing the courthouse to ashes, would be deterred from parking there...
Much of what is happening is an expansion of police and government authority because they want to expand their authority and will take any oppoortunity to do so. It has nothing to do with security.
Sorry for the rant, but I take this kind of thing personally.