Why Did an Ex-Marine Open Fire in a California Bar?

When gunmen whose names are best forgotten killed 12 classmates and one teacher at Columbine High School in 1999, I never imagined that a mass shooting on that scale would be a minor news story.

Almost 20 years later, the latest massacre of like size is destined to fade quickly from headlines. The dead include 12 innocents and one gunman, all killed at a Thousand Oaks, California, bar where college kids line danced to country-and-western songs. Sergeant Ron Helus died heroically as the first police officer on the scene, rushing inside to try to stop the gunman rather than waiting. In the wee hours Thursday morning, as a still-unknown number of victims lay inside, local-TV-news reporters stood asking practiced questions of survivors who had stuck around. Some described having imagined and prepared for such an emergency.

With the killer not yet known, people speculated about the motive: Was it a disgruntled employee? A jealous boyfriend or husband? A person radicalized online by Islamists, or white supremacists, or misogynists? A person suffering from mental illness? Later Thursday, the Los Angeles Times reported that the killer was “a former U.S. Marine machine gunner who may have suffered from post-traumatic stress disorder.” He had served a combat tour in Afghanistan and was 28 years old.

Read: A mass shooting in one of the ‘safest cities in America’

“Are military veterans more likely for shooting sprees?” The San Diego Union-Tribune asked last year, citing eight occasions when a veteran of one of the wars fought since September 11, 2001, perpetrated a mass killing.

Experts cautioned against sweeping conclusions, stressing that there is no evidence that veterans of the wars in Iraq or Afghanistan are any more prone to violence than the general population; the overwhelming majority of those who return home from war are thriving.

“Combat veterans, on the whole, are not going to be lethally violent,” said Shoba Sreenivasan, a University of Southern California psychology professor who was the lead author of a 2013 paper examining the topic. She noted that a small segment of combat veterans may be triggered to commit violence because of their battle experiences. These individuals often have mental or emotional issues other than war-related post-traumatic stress disorder.

“There are some people—a very tiny, tiny percentage—whose combat experience creates some mental instability, along with other factors like drugs and alcohol, that then may contribute to lethal violence stateside.”

Thomas Burke, a pastor in the same US Marine Corps regiment where the Thousand Oaks killer served, spoke to CNN about their time in intense combat. “PTSD doesn’t create homicidal ideation,” he argued. “We train a generation to be as violent as possible, then we expect them to come home and be OK. It’s not mental illness. It’s that we’re doing something to a generation, and we’re not responding to the needs they have.”

Read: Should veterans with PTSD be exempt from the death penalty?

If so, what are those needs? The killer tried college but failed to earn a degree. He was reportedly a patron of the bar, but obviously turned on that community, if it was one for him. Absent better answers about whether this man was among the tiny percentage who wouldn’t have killed at home but for being sent to kill “over there,” or what exactly would have altered the course of his life once home, it seems safe to at least conclude that his combat experience made him a more skilled assailant.

And whatever the factors in this particular case, it is past time that America embarked on a sustained experiment in waging foreign wars only as a last resort—and did more to support those it sends abroad to fight when they come back home.