I've got no problem with photographers being scrutinized, since I can see reasons why terrorist planners would need reliable photos of their target's infrastructure and also how the security forces respond to casual lingering people operating obscure equipment in proximity to a target. If I come into a subway with some strange contraption, I hope I'm questioned -- if only they had questioned the guys who spread Saren Gas on the Tokyo subway as to why they had plastic sheeting, fans, and gas masks for instance. The Mumbai Hotel terrorist planner posed as a photographer... there are likely plenty of other instances as well.
Owning fertilizer and diesel fuel is not a crime, and millions of farmers do just that, but if I'm observed wheeling a couple of drums into your apartment building's parking garage, shouldn't there be a mechanism in place for the security people to question me about it?
These laws have to be broad enough to accommodate new, odd potential threats. That the local cops and guards go out of their way to hassle a clean-living photographer is unfortunate -- but it's more a matter of political correctness. If they only stopped 20-yr old swarthy males then they'd be guilty of stereotyping. Just like our Grannies have to undergo these ridiculous airport searches, it's a more a matter of the police practicing performance art than it is at rooting out real terrorists.
I say leave the security laws in place, just hire some police and guards with some common sense.