Contradictions abound in the available data about America's gun violence epidemic. The numbers do not point to one clear trend. They do not really tell us whether we are managing risk any better. They are confusing. They often contradict the confident assertions made by partisans. There is plenty of fruit to cherry pick.

So what do we actually know?

The first thing to know is that violent crime of all types is down. In the United States, there are half as many gun homicides today as there were in 1997.

Why? Steven Pinker has a number of theories that try to bridge the gap between psychology, evolution, and criminology. More (and better, but more aggressive) policing has helped; new technology like cell phones make it easier for people to get help when they're shot, easier for police to track criminals, easier for emergency room doctors to more effectively treat gunshot wounds. The decline in the use of lead, which, it seems, fritzes the brain of people who grow up with it in their walls, probably helped too.

But wait. Black people are killed by guns at twice the rate of white people, and more than twice the rate of Latinos.

Do existing gun laws help? Maybe. Between 1994 and 2012, according to stats provided by Igor Volsky of Think Progress, 2.4 million fugitives, felons, and domestic violence perpetrators were stopped by background checks from purchasing weapons. On the other hand, the Government Accountability Office found that 1,300 people whose potential connections to terrorism were deep enough to get them watchlisted were able to buy guns; 90 percent passed the FBI background check.

As I said, contradictions abound.

The same is true of Americans' rather confused views on gun laws.

A large majority of Americans support specific gun control measures, like federal tracking of gun sales, when asked.

But most Americans don't think gun laws make much of a difference, anyway.

And half see the right to bear arms as being under threat now. This number has been growing steadily, according to a Washington Post analysis of the data. And 57 percent of Americans think that stricter gun laws would empower the federal government to a dangerous degree.

Ideological polarization has increased; more Republicans now oppose gun laws, while the percentage of Democrats who feel one way or the other has stayed relatively constant.

Guns are everywhere. There are 300 million of them in circulation in America, which translates to about 88 guns for every 100 people. Unless Americans are naturally more violent than Europeans and Australians, the presence of so many guns is the main reason why, despite the decline in gun violence, America remains so much more violent than other countries with high standards of living.

This can lead to some scary statistical marshaling.

The U.S. accounts for 87 percent of the world's gun death rate for children under 14.

What percentage of gun deaths comes from mass shootings versus gang/drug violence or domestic violence situations? A fairly tiny fraction. Miniscule, even. Slightly more than one percent, Terrorism? Less than one half of one percent.

The plurality of gun deaths are suicides, Vox notes. And yes: Living in a household with guns makes it far more likely that you'll become a victim. Accidentally killing someone else with a gun accounts for a little less than two percent of all gun deaths each year.

The mentally ill committed, at most, five percent of all gun homicides each year.

Are mass shootings increasing? Probably not.