One of the arguments that the NRA has used to deny gun-control legislations is that the best solution to "bad guys" with guns is "good guys" with guns. Here's an example where that did not work, surprisingly.
My condolences to the families of those killed.
The NRA and gun manufacturing industry, who have lobbied successfully to end any reasonable gun control, are responsible for these deaths.
They are terrorist organizations, clearly a threat to public weal.