When I was a Cyber-Security masters student in a NSA certified program, I wrote a white paper about using technology to hack the City of NYC train transit system and create a public safety nightmare. If critical train transfer points were shutdown during rush hours, it would be possible to route trains using a DDOS attack on all types of communication devices. As passengers and station staffers seek optional underground travel pathways, riders could be forced to flood and congest train station platform drop-off/pickup locations. As platforms become overcrowded, folks will eventually trip and/or fall unto tracks to be killed. While folk at the street level continue to go underground, nobody underground is allowed to tell folks at the street level to stop coming down. Once emergency services and transit worker communications devices are compromised, it would be impossible grasp a boots-on-the-ground analysis of the public risk on the platforms. Trains can be controlled not to open doors and been re-routed at will to create more confusion. The current national security event reminds me of the threat vector I wrote about. While the bad acts may pause operations, this may not be over yet because someone planned this big attack expected a major success.