For instance, there is this "Catch 22" problem. If someone shoots a potential mass shooter before they begin, theoretically a mass shooting never took place.  With that being the case one can't definitively claim it was prevented. Or conversely, if a mass shooting is underway and is then stopped by an armed civilian, literately the mass shooting wasn't prevented. Because they will claim, it already had happened. This "Catch 22" makes it technically impossible to stop a mass shooting.

It is simply mental gymnastics by the people who want to disarm the general population. Because if you stop a mass shooting as apparently happened with Eli Dicken, the armed shopper in Indiana, you would still have saved countless lives. Since the shooter in that situation was well equipped and his first victim was caught totally off guard and was also an armed civilian, who knows how many more people he would have killed. And who knows if that armed citizen had been more aware if the shooter would have even been able to kill anyone. No one really knows how many would have died because Eli responded effectively and saved us from reading a longer list of victims. Eli was carrying a pistol because it is NECESSARY for SECURITY. Do you remember where you read those two words?

What irked me about Eli's circumstance is that the media tried to paint him as a bad guy because he violated a "rule" against being armed on the shopping mall property. Oh, my God! I'm sure that if the talking heads would have been in the crowd of endangered people they would have chastised Eli for being such a threat to the mall owners. Gun free zones are crime spree zones.