Wednesday marks the 17th anniversary of the Columbine High School massacre — the terrible day in 1999 when Eric Harris and Dylan Klebold killed 13 and wounded dozens more before killing themselves in Colorado.

In the strangely American phenomenon of mass shootings, Columbine comes up again and again. As I wrote last year:

It was Columbine that changed everything…a horrifying event that occurred just as the Internet was taking root in the lives of ordinary Americans.
Harris, 18, and Klebold, 17, were savvy about incorporating the Internet into their terrorism, posting rants about the world on a Trench Coat Mafia website. Their digital footprints gave investigators insight into their minds and motives.

Their rantings — especially those written by Harris, the ringleader of the attacks — are disturbing and cruel, showing no empathy or remorse.  The evil seems unambiguous — that is, until you read the cache of sweet, wistful and carefully composed essays that Harris wrote a couple years before the attack.

I stumbled on them the other day in a publicly accessible database of school shooters maintained by Peter Langman, a psychologist and author of two books on school shootings. Langman told me the writings are crucial to understanding what he believes really motivated the Columbine massacre.

In a 1997 essay, Harris wrote:

The first home I lived in was located in a largely wooded area, so we didn’t have many neighbors. Oscoda is a very, very small town. Of the three close neighbors I had, two of them had children my age. Every day we would play in the woods, or at our houses. We would make forts in the woods or make them out of snow, we would ride around on our bikes, or just explore the woods. It was probably the most fun I ever had in my childhood.

Later in the essay, after detailing several moves his family made, Harris shows a remarkable sense of nostalgia for old friends:

Loosing (sic) a friend is almost the worst thing to happen to a person, especially in the childhood years. I have lived in many places, but the last three places have been the most fun and the greatest experiences of my childhood. Although memories stay with you, the actual friend doesn’t. I have lost many great friends and each and every time I lost one, I went through the worst days of my life.

These early writings seem difficult to reconcile with the Harris prose that came later. Harris wrote about killing “all retards,” warning that “if you got a problem with my thoughts, come tell me and i’ll kill you, because………god damnit, DEAD PEOPLE DONT ARGUE!” He especially despised the cool kids. “It has been confirmed, after getting my yearbook,” he writes, “that the human race isn’t worth fighting for, only worth killing.”

Langman thinks the early works are evidence that the persona Harris (and the media) embraced — that of an ostracized loner with a terrible childhood — was a kind of fiction. The later writings, Langman thinks, are a “search for justification.”

“My suspicion is that he rewrote his life story to justify his rage and his need for violence,” Langman said.

Here's a look at some of the most notable U.S. mass shootings. (Alice Li/The Washington Post)

So what was he covering for?

Langman has an idea. He calls it “damaged masculinity” and he thinks it is overlooked not just in the Columbine case but in many other mass shootings — an important observation considering that most mass shooters are male.

Harris was born with a birth defect in his leg. He also had a chest deformity that required surgeries just before high school. He had a noticeable, sunken chest. His hopes to follow his father into the military — to be a tough guy, a Marine — were likely to be unrealized.

Guns, he reasoned, could give him power and control.

“I am (expletive) armed,” he wrote in his journal. “I feel more confident, stronger, more Godlike.”

What was he without guns?

“The weird looking Eric kid,” Harris wrote.

In examining the masculinity idea in one of his books, Langman quotes psychoanalyst Erich Fromm on what makes someone sadistic: “He is sadistic because he feels impotent, unalive, and powerless. He tries to compensate for this lack by having power over others, by transforming the worm he feels himself to be into a god.”

Harris became godlike 17 years ago today, choosing who lived and who died.

Langman has other examples of damaged masculinity and the guns cure. Take Elliot Rodger, who called himself the “kissless virgin.”

In 2014, Rodger killed six near the University of California-Santa Barbara. Before the shooting, he wrote: “I compared myself to other teenagers and became very angry that they were able to experience all of the things I’ve desired, while I was left out of it. I never had the experience of going to a party with other teenagers, I never had my first kiss, I never held hands with a girl, I never lost my virginity.”

Then he bought a Glock.

“After I picked up the handgun, I brought it back to my room and felt a new sense of power. I was now armed,” he wrote. “Who’s the alpha male now, bitches?”

The mass shooter.

WATCH: 374 mass shootings in 365 days in one extraordinary graphic (Gillian Brockell, Julio Negron/The Washington Post)

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