Well then, more of these should be sold to the general public, because it sure wasn't very effective today.
I recently traveled to Los Angeles, arriving via the Metra, into Union Station. There are zero hands-on physical security inspections. Should a bad actor decide to act upon such vulnerabilities, dozens, if not hundreds of innocents could be harmed. Imagine boarding a train and once out of station, what could happen if an evil doer started whacking UNARMED people in the last car from front to rear? The confined space would aid the diabolical in their goals. I'm actually quite disturbed by my own dark "what if" hypothesize. Note to self: carry concealed, whether legally permitted or not!