Urban centers are hubs and pinnacle points of public mass transportation. Mass transportation compresses an already high-density population into high density areas and modes of transportation which are honey pots for “bad actors” wishing to achieve maximum casualties and hysteria with minimal effort and resources.
Public transportation hubs and vehicles are soft targets
There are both technological and human behavioral aspects that are very effective at reducing or eliminating the adverse effects of the evildoers. Situational Awareness is the most critical tool in this battle for freedom and safety. Practicing a heightened awareness is critical to assuring your safety.
The USA Department of Homeland Security initiated a program under their science and technology section with the focus on:
Surface transportation such as subway systems can be a unique security challenge due to the large crowds of travelers and the open, unstructured environment. Public safety officials (including mass transit operators, mass transit police, and state and federal law enforcement teams) need a capability to detect potential threat items on persons and in bags without negatively impacting the speed of travel. S&T is developing technology to meet this challenge with the Surface Transportation Explosive Threat Detection Program, helping provide a layered, integrated capability to detect and mitigate the explosive threat at the speed of the traveling public.