Actually, I happen to work for the Army so I am often near well armed "grunts" with access to that off switch. It's a judgment call, but I assume walking around the Pentagon is probably safer than driving which I am also willing to do. More to the point, I think being respectful to well armed people is prudent, hiding under the bed is pointless. So, while I recognize the risk to life and limb at some point you need to focus on risk mitigation rather than avoidance.

PS: To put this into perspective, one of the guys I work with was there for 9/11. He sustained significant injury while several people in the room with him died. Yet, he is also willing to work in the building and most people in the building where not harmed.