The concluding sentence does not make sense.

After railing against the NRA, the piece concludes: "Killers like the one in Las Vegas are the... lone wolves of a political movement that has lost all sense of common decency."

Hello?

How on Earth is the Vegas mass murderer a "lone wolf" on behalf of the NRA? How is that Vegas mass murderer a "lone wolf" for any political movement?

Seriously, did he leave a manifesto? Did he leave a list of political demands? Did he have a documented history of voting exclusively for extremist one-note candidates?  

That "lone wolf" claim is made without evidence and it makes no sense. A lone wolf is a terrorist whose action is made in support of a defined political ideology. What political ideology are the editors trying to invoke, what, maybe the anti-country-music party?

The Vegas mass murderer was squarely just that, based on what is known. The editors, like some columnists, strain, strain and strain again to ram him into the "terrorist" slot.