The producers of Sex and the City decided this summer not to use an episode in which a terrorist threat prevents Sarah Jessica Parker's character from getting on the subway, deeming it an inaccurate depiction of New York City life.
But while many are relieved by the so-far, so-good track record of public transportation since Sept. 11, some urban dwellers say they still feel anxious about the possibility of a mass-transit attack.
"The D.C. police have made a lot of efforts with regard to transit safety," said 25-year-old Washington resident Michelle Crispino. "But I'm still a little nervous."
New York City speech therapist Lori Marinelli is so worried about terrorism that she no longer uses the subway system.
"I haven't been on it since Sept. 11," said Marinelli, who lives in Queens. "Actually, I did once, a few days after the attacks, because I wanted to get my courage up. But I felt very nervous and suspicious the whole time. I never did it again."
Marinelli said she feels security is simply too lax on New York's subways and buses. She cited the homicide bombings in Israel and the 1995 subway attack in Tokyo, in which the apocalyptic Aum Shinrikyo cult killed 12 people in a sarin gas attack.
"I would feel better if they just had a police officer in each car," she said.
Metropolitan Transportation Authority spokesman Tom Kelly said the New York City commuter system is indeed on heightened alert -- and that new security measures such as canine patrols have been put in place in major train terminals.
"We're doing everything humanly possible to ensure the safety of our customers," he said, declining to give more specific information.
But if New York is anything like other major cities, there may well be more than just a few officers on the subway. They are difficult to spot because they look like regular people.
As part of its stepped-up transit security plan, the Metropolitan Transit Authority in Washington, D.C., has added hundreds more plainclothes and uniformed police officers, and removed trash bins from train stations, replacing them with new explosion containment cans.
As part of a pilot program, the city is also training all employees in unknown substances and adding new canine explosion detection dogs, as well as digital cameras, on 100 of 1,440 buses.
Washington MTA spokesman Steven Taubenkibel said the agency, with an eye on Japan's sarin gas attack, was working even before Sept. 11 to install an underground chemical detection system.
"We knew then we had to begin thinking the unthinkable," he said.
Two Washington subway stations have chemical sensors -- and the goal is to have them in all stations, Taubenkibel said.
Chicago Police spokesman David Bayless also declined to offer any specific security information. But he did say police have become more visible in the transit system since Sept. 11, checking out subway tunnels with canine detection dogs and sealing off potential terrorist entry points.
In Los Angeles, transit spokesman Marc Littman said both uniformed and plainclothes officers are in use on the system, in addition to security cameras in all 50 rail stations and on many current and all new buses.
On the trains, there are no cameras -- but there are some officers. The city is also installing a barrier system to replace its current underground honor system (there are no turnstiles), and is working with the FBI and Secret Service to prepare for transit emergencies.
But despite these efforts, Littman said there's no way to provide 100 percent protection.
"I won't lie and say nothing can happen. No transit system -- New York, Chicago -- can prevent someone dead-set on causing havoc to the system. All we can do is try to throw some deterrents here and there," he said.