The recent attack on a European high-speed train provides a sobering reminder that no other form of transportation has the kind of security air travel does — a hard fact unlikely to change.
"The challenge of securing mass transit is one that will persist," says David Heyman, a former top official at the Department of Homeland Security. "You have a system that is open to the public and requires rapid turnaround of people in subways and rail."
Belgium is increasing baggage checks and uniformed patrols on its high-speed trains as a result of Friday's attack on an express train from Amsterdam to Paris. Passengers, including three Americans, subdued the attacker.
A spokesman for the Department of Homeland Security said Monday no new warnings were issued in the U.S. as a result of the incident and that no new threats had been detected.