I agree with the comments here that this sort of deliberate use of a light aircraft as a weapon is pretty limited in the (physical) damage it can cause.
Problem is, we're all sensible, rational sorts who can hopefully take a step back (Despite being involved) and draw a rational conclusion, while the majority of the US public probably won't have such a reasonable reaction - and if I know the media, they'll make sure of it in their usual style.
Yes, of course WE know GA isn't a threat, but I think a lot of people are simply looking for something to be afraid of...