Doug --
Riot control is not a civilian function, period, end of story. Worrying about it as you do here failry conssitantly makes about as much sense as buying your own fire engine "just in case"... heck even that sounds sensable compared to this...
If there ever comes a day when riots must be stoped by civilian force then we are all in a world of hurt...
Yes riots do happen, they and cival unrest in general is worth thinking about but in general get the heck out (OR be a happy, dead, proud property owner....) and only use a weapon if you have to... and only for egress from whatever mess you have found yourself in.... if we had to deal with a riot my first question would be how much fuel is in my truck where can I get some more, second woudl be what direction are we going in, and weapons would be with me but would be a teartary concern...
Really Doug, I was down at Katrina, I saw serious civial unrest, breakdown of society all of that jazz... it WAS shocking, however, what you worry about and propose is so FAR beyond that it defies words, and the manner in which you frame questions and resonses offften leaves me thinking that you are exaclty the kind of lose cannon that would make a bad situation worse and or get someone needlessly killed.