Americans have blamed many culprits, from mental illness to inadequate security, for the tragic mass shootings that are occurring with increasing frequency in schools, offices and theaters across the U.S.

Yet in our nation’s ongoing conversation about the root causes of gun violence, the makers of guns are hardly ever mentioned. As a public health researcher, I find this odd, because evidence shows that the culture around guns contributes significantly to gun violence. And firearm manufacturers have played a major role influencing American gun culture.

To help spur this much-needed discussion, I’d like to share some critical facts about the firearm industry that I’ve learned from my recent research on gun violence prevention.