Is a gun necessary to commit a mass atrocity?

Some ardent proponents of gun control think taking firearms away from people would make them less violent. Or at least less effective at violence. In short, in those people's estimation once the population is disarmed you are going to see less violence, or at least less violence where multiple people are killed or injured in one episode. Some even sound off with statements like, "You've never seen a drive-by stabbing, have you?" Which may be technically correct though a charge by a sabre-wielding cavalry fighter comes pretty close. But I am getting a bit off track here.

So let me address the thesis above head on. No, I have not seen, or, for that matter, heard of a drive-by stabbing. But I have certainly heard of plenty of instances of mass criminal atrocities committed without a firearm involved. For example, a few days ago a man went on a stabbing spree in Wisconsin, killing one and injuring four, some of them rather seriously. In 2014, eight blade-wielding terrorists killed 35 and injured over 130 people in Kunming, China. Waukesha Christmas Parade attack and Nice Bastille Day atrocity were both committed by a single terrorist using a vehicle as a weapon. So clearly, to answer the title question, a firearm is not required to commit an act of mass murder.

Now is it true that a firearm helps some people perpetrate an act of violence they would otherwise be incapable of? Perhaps - especially when it comes to shooting someone from a distance. But in plenty of instances mass murderers shoot their victims from a distance of under 5 m, or even under 2 m. In that case, while this is not as "upclose and personal" as gutting someone with a knife, it is no further removed than a vehicle driver would be from pedestrians on the other side of the vehicle's front bumper. And, at least based on my experience, while some data exists that show that frequency of gun violence goes down with gun confiscation campaigns (like the mass disarmament that took place in Australia about 20 years ago) there is none that I could find indicating correlation between low levels of civilian firearms ownership and low levels of crime in society. Which likely means, it is other factors that shape the overall crime picture and the only thing that happens when firearms are not available is that bad guys switch to using other tools to perpetrate violence they would have perpetrated anyhow.

However, guns are essential for leveling the field for a potential crime victim. And that is one of the strongest arguments in favor of civilian firearms ownership.