This was on Drudge today...
First off, this young man held his constitutional ground as well as anyone. His continued filming throughout the event was pretty gutsy, only to have officers make fools of themselves when he wouldn't give in to intimidation. Putting clothing over the lens was almost comical.
Second, if citizens are someday prevented from photographing common things in the public world from public places the terrorists have definitely won. The cops mentioned 9/11, presumably referring to the surveillance videos shot in Manhattan, but they were not of transit vehicles. Do those cops believe that tourists should no longer be able to film the Empire State Building on their once-in-lifetime vacation? If so the terrorists have won.
Now, in defense of the police the intelligence cache grabbed in bin Laden's villa did mention attacks on public transportation, including railroads, so it's not surprising our law enforcement professionals might be a little ancy about dudes filming the rails right now. But that's where police work comes in. We can't have a society where police indiscriminately harass and detain law-abiding citizens and demand their papers just for videoing in the middle of a city.
While transit police harass the hearing-impaired train buff in Baltimore thieves are actually out stealing the rails right off the tracks. This one in Massachusetts, and this one in California. Desperate times and desperate measures apparently.