The other issue is that a jihadi looking to slaughter infidels would have amassed a much higher body count simply going door-to-door and killing everyone in his path. In Bombay, that's exactly what they did, with 11 guys amassing a body count of 160+ victims.
“..going door-to-door and killing everyone ..”
May have been planned different if Bombay had a 2nd amendment though. That method would have brought a quicker end I would think here in the US.