New York city has decided that they want to photograph and scan every vehicle that enters Manhattan:

The Police Department is working on a plan to track every vehicle that enters Manhattan to strengthen the city’s guard against a potential terror attack, the department’s chief spokesman said.

The proposal — called Operation Sentinel — relies on integrating layers of technologies, some that are still being perfected. It calls for photographing, and scanning the license plates of, cars and trucks at all bridges and tunnels and using sensors to detect the presence of radioactivity.

Data on each vehicle — its time-stamped image, license plate imprint and radiological signature — would be sent to a command center in Lower Manhattan, where it would be indexed and stored for at least a month as part of a broad security plan that emphasizes protecting the city’s financial district, the spokesman, Paul J. Browne, said. If it were not linked to a suspicious vehicle or a law enforcement investigation, it would be eliminated, he said.

I'm guessing that not that long after this system is put into place, the New York Transit Authority will propose a new toll system on vehicles coming and going into Manhattan... but that's just a crazy guess.  As for how safe this will make the city, we all know the answer is that it will actually decrease safety by flooding police with more information than they can do anything about, and create false positives that will take manpower away from methods that can actually produce leads.

But hey... everybody enjoys a good Security Theater show right?