Mass shootings in America seem like a never-ending nightmare.
On Saturday, a shooting in El, Paso, Texas, killed 20 people and injured 26 more. On Sunday, a shooting in Dayton, Ohio, killed at least 10 and injured 26 more. The weekend before, a shooting in Gilroy, California, killed four and wounded 13 others, while yet another shooting in Chippewa Falls, Wisconsin, killed six and injured two.
That doesn’t even account for the average 100-plus gun deaths that aren’t part of mass shootings but happen every day in the US.
Why does this keep happening? In the aftermath of a shooting, many Americans focus on the shooter’s motive. That leads to some legitimate questions, like whether the gunman in El Paso was motivated by white supremacy and racism that President Donald Trump has enabled, or what role, if any, mental illness played. It’s also led to some less valid contributions, such as House Minority Leader Kevin McCarthy and Texas Lt. Gov. Dan Patrick’s bizarre comments suggesting violent video games are to blame.
But the reason for the ceaseless death toll is simpler: It ultimately comes down to America’s lax access to a large supply of guns.
Many factors can of course play a role in any individual shooting. But when you want to explain why America sees so many of these mass shootings in general — more than 250 so far in 2019, by one estimate — and why America suffers more gun violence than other developed nations, none of these factors gives a satisfying answer. Only guns are the common variable.
To put it another way: America doesn’t have a monopoly on racism, sexism, other kinds of bigotry, mental illness, or violent video games. All of those things exist in countries across the world, many with much less gun violence. What is unique about the US is that it makes it so easy for people with any motive or problem to obtain a gun.
America’s gun problem, briefly explained
It comes down to two basic problems.
First, America has uniquely weak gun laws. Other developed nations at the very least require one or more background checks and almost always something more rigorous beyond that to get a gun, from specific training courses to rules for locking up firearms to more arduous licensing requirements to specific justifications, besides self-defense, for owning a gun.
In the US, even a background check isn’t an absolute requirement; the current federal law is riddled with loopholes and hampered by poor enforcement, so there are many ways around even a basic background check. And if a state enacts stricter measures than federal laws, someone can simply cross state lines to buy guns in a jurisdiction with looser rules. There are simply very few barriers, if any, to getting a gun in the US.
Second, the US has a ton of guns. It has far more than not just other developed nations but any other country, period. In 2017, the estimated number of civilian-owned firearms in the US was 120.5 guns per 100 residents, meaning there were more firearms than people. The world’s second-ranked country was Yemen, a quasi-failed state torn by civil war, where there were 52.8 guns per 100 residents, according to an analysis from the Small Arms Survey.
Both of these factors come together to make it uniquely easy for someone with violent intent to find a firearm, allowing them to carry out a horrific shooting.
This is borne out in the statistics, which show America has far more gun violence than other developed nations. The US has nearly six times the gun homicide rate of Canada, more than seven times that of Sweden, and nearly 16 times that of Germany, according to United Nations data for 2012 compiled by the Guardian. (These gun deaths are one reason America has a much higher overall homicide rate, which includes non-gun deaths, than the rest of the developed world.)
If having so many guns around actually made the US safer, as the National Rifle Association and pro-gun politicians claim, America would have one of the lowest rates of gun violence in the world. But the statistics suggest that, in fact, the opposite is true.
The research, compiled by the Harvard School of Public Health’s Injury Control Research Center, is also pretty clear: After controlling for variables such as socioeconomic factors and other crime, places with more guns have more gun deaths. Researchers have found this to be true not just with homicides but also with suicides (which in recent years were around 60 percent of US gun deaths), domestic violence, violence against police, and mass shootings.
As a breakthrough analysis by UC Berkeley’s Franklin Zimring and Gordon Hawkins in the 1990s found, it’s not even that the US has more crime than other developed countries. This chart, based on data from Jeffrey Swanson at Duke University, shows that the US is not an outlier when it comes to overall crime:
Instead, the US appears to have more lethal violence — and that’s driven in large part by the prevalence of guns.
“A series of specific comparisons of the death rates from property crime and assault in New York City and London show how enormous differences in death risk can be explained even while general patterns are similar,” Zimring and Hawkins wrote. “A preference for crimes of personal force and the willingness and ability to use guns in robbery make similar levels of property crime 54 times as deadly in New York City as in London.”
This is in many ways intuitive: People of every country get into arguments and fights with friends, family, and peers. Every country has extremists and other hateful individuals. But in the US, it’s much more likely that someone who’s angry or hateful will be able to pull out a gun and kill someone, because there are so many guns around and few barriers to getting the weapons.
Researchers have found that stricter gun laws could help. A 2016 review of 130 studies in 10 countries, published in Epidemiologic Reviews, found that new legal restrictions on owning and purchasing guns tended to be followed by a drop in gun violence — a strong indicator that restricting access to guns can save lives. A review of the US evidence by RAND also linked some gun control measures, including background checks, to reduced injuries and deaths. A growing body of evidence, from Johns Hopkins researchers, also supports laws that require a license to buy and own guns.
That doesn’t mean that bigots and extremists will never be able to carry out a shooting in places with stricter gun laws. Even the strictest gun laws can’t prevent every shooting.
Guns are also not the only contributor to violence. Other factors include, for example, poverty, urbanization, alcohol consumption, and the strength of criminal justice systems.
But when researchers control for other confounding variables, they have found time and again that America’s loose access to guns is a major reason the US is so much worse in terms of gun violence than its developed peers.
So America, with its lax laws and abundance of firearms, makes it uniquely easy for people to commit horrific gun violence. Until the US confronts that issue, it will continue to see mass shooting after mass shooting.
For more on America’s gun problem, read Vox’s explainer.
Correction: This post originally included an overestimate of the 2019 mass shootings.