Fair enough. Correlation does not necessarily infer causation. Despite you're foolish comparison to the number of reality shows and crime rates.You'd have to do a lot more to prove those two things are related.
Otherwise we could say things like the number of reality shows has also increased in that same time period therefore reality shows prevents crime.
I think people need to stop trying to justify owning guns. I'm fine with people owning guns. I'm not fine with people making up reasons to own guns.
There are many studies which have indicated that the use (or potential use) of firearms in acts of self defense are upwards of 1 million per year. Sure many of those studies are from the 1990's but it's clear that having the ability to use the firearm in self defense far outweighs the use of guns for sinister reasons. Let's also be clear to discern between legal and illegal firearms use. The vast majority of homicides in the United States are at the hands of a gun that is illegally possessed.
The CDC concluded in 2013 that legal firearm possession is an essential crime deterrent. But I fully support that anyone needs to qualify before they are granted a firearms license. That would include background checks, medical history and proper training.