Thanks for the thoughtful situation description. Clearly, it doesn't have to be something as exotic as a dirty bomb. Many things could cause an urban panic nightmare. Riots for one (been there).
I will have to rethink my car kit and EDC with this sort of thing in mind.

On a more mundane level I've tried to make my EDC include things for the little emergencies of life. A couple of iodine pads and a band aid have come in handy more than once. What about getting turned around on back country roads (with your wife getting uptight)? My button compass has come out in that situation and proved usefull in telling which way I will be going if I turn left or right. Even drinking water and a couple of Tylenol may save your day if not your butt.
Then there is the pocket knife/tool. Came in handy lots of times.
Things like that make me more likely to carry my EDC whenever I am out.