So news that security could be tightened even more in response to a new terrorism warning didn't faze most residents, who accepted it as a necessity after the 2001 terrorist attacks.
"If it can help make us a whole lot safer, the inconvenience is worth it," said Queen Owens, a 44-year-old Boston medical assistant. "After Sept. 11 (search), I think we should all be worried a little bit. What's to prevent a surprise from really happening again?"
The FBI and Homeland Security Department officials said Friday they had received uncorroborated intelligence that trains and buses in major U.S. cities may be targeted by terrorists using bombs hidden in bags or luggage.
The warning was taken in stride in other cities as well.
Gabriel Banda, 19, of Dallas, who rides the bus every day, said he would not vary his plans because "What are the chances of that happening here?"
He was skeptical of any increases in security that include baggage screening. "Almost everyone in DART is carrying a bag. To search all those bags on one ride, it just would annoy everybody."
Massachusetts Gov. Mitt Romney asked the state public safety secretary to work with transit authorities to develop "more robust plans" to protect citizens on public transportation. He said officials would consider a number of options, including baggage screening and limiting access to parking facilities.
Dallas-based Greyhound Lines Inc. said Friday it already had a plan in place to deal with security for each terror threat level.
However, when a bulletin is issued, like the one given to law enforcement agencies Thursday night, company officials tell employees to be extra vigilant, said company spokeswoman Lynn Brown.
Dallas Area Rapid Transit Police Chief Juan Rodriguez said the 193-officer force has taken no extra precautions because it has been on a higher level of alert since the 2001 attacks.
In Chicago, a spokesman for the Metra commuter rail service said security was increased after Sept. 11 and last month's train bombings in Madrid, and that those security measures remained in place.
Spokesman Tom Miller said it would be difficult to secure everything all the time.
"The question is asked, 'Why can't you seal off train stations like airports?' We have a completely open system, with over 200 stations in our system. They are impossible to seal off like airports," he said.
Back in Boston, Mark Brown, 45, a graphic artist from Plymouth, Mass., said there might be inconveniences from increased security, but "that's the life that everyone's been living all over Europe and everywhere. And that's what they've made us adapt to. We're lucky we've gone this long (without restrictive security measures). Very lucky."