As Americans debate how the country should respond to gun violence, they should not lose sight of the biggest category of firearm deaths: suicides. About two-thirds of people killed by guns, or 20,000 a year, kill themselves.

The rate at which Americans commit suicide with guns has been increasing for several years, even as the rate of gun homicides has declined. Research shows that the increase is correlated with higher gun ownership. Public health experts say ready access to firearms makes it easier for people to act on suicidal thoughts. And about 85 percent of suicide attempts that involve guns are successful, compared with less than 3 percent of those involving drug overdoses. Over all, guns were used in about half of the 41,000 suicides in 2013, the latest year for which there is data from the Centers for Disease Control and Prevention.

These numbers are all the more tragic because suicide is a leading cause of death among young people. And contrary to the conventional wisdom that people who are determined to end their lives will find a way to do so, 90 percent of people who survive suicide attempts do not eventually die by suicide.

The country could reduce the death toll by enacting better safety policies and investing in education campaigns. A good place to start would be to encourage gun owners to properly secure their firearms, by placing them in safes and storing them separately from ammunition. This would make it harder for teenagers, who are more impulsive, to commit suicide and help reduce the toll of unintentional gun deaths, estimated at about 500 in 2013.