Perhaps not, but I wasn't speaking of the probability of an incident so much as the actual function of shooting/acting if the situation arose. In actuality, except for one day in 2001, we haven't had any really nasty incidents involving airplanes. Until 9/11, it really wasn't something a reasonable person would consider.
Of course, if the terroristic ones get the chance, the mall may not be such a far-fetched target. Israel is a good example.