In “No Ordinary Violence,” a new article on his site, Sam Harris tries to classify people who commit mayhem and murder.

His attempt was inspired by a media question:

After the Boston Marathon bombing, a journalist asked me, “Why is it always angry young men who do these terrible things?” She then sought to connect the behavior of the Tsarnaev brothers with that of Jared Loughner, James Holmes, and Adam Lanza. Like many people, she believed that similar actions must have similar causes. But there are many sources of human evil.

Harris sees four main groups of perpetrators (though he readily admits that one perp can have more than one psychological “driver”). The categories are — and I’m paraphrasing —

Killers who are outright irrational and/or delusional, à la Aaron Alexis or Jared Loughner.

Prototypically evil sociopaths, such as (let’s say) Ariel Castro or Ted Bundy.

“Normal” people for whom ordinary selfishness and fear are “magnified” to the point that they rationalize their violent deeds. “Think of a boy growing up in the inner city who joins a gang for protection, says Harris, “only to perpetuate the very cycle of violence that makes gang membership a necessity.”

Finally, ideologues who kill for purity, to rid the world of those who violate political or religious orthodoxy. Examples include Anders Breivik and Mohammad Atta.

Regarding that last group, Harris writes,

Some of these belief systems are merely political, or otherwise secular, in that their aim is to bring about specific changes in this world. But the worst of these doctrines are religious — whether or not they are attached to a mainstream religion — in that they are informed by ideas about otherworldly rewards and punishments, prophecies, magic, and so forth, which are especially conducive to fanaticism and self-sacrifice.

Ever since he waded into the debate about Islam and violence, Harris has had more than his fair share of detractors.

Whenever I point out the role that religious ideology plays in atrocities of this kind — specifically the Islamic doctrines related to jihad, martyrdom, apostasy, and so forth — I am met with some version of the following: “Bad people will always do these things. Religion is nothing more than a pretext.” This is an increasingly dangerous misconception to have about the human mind. Here is my pick for the most terrifying and depressing phenomenon on earth: A smart, capable, compassionate, and honorable person grows infected with ludicrous ideas about a holy book and a waiting paradise, and then becomes capable of murdering innocent people — even children — while in a state of religious ecstasy. Needless to say, this problem is rendered all the more terrifying and depressing because so many of us deny that it even exists.

I like that analysis. And I like this just as much:

There is no clear line between what members of the Taliban, al Qaeda, and al Shabab believe about Islam and the “true” Islam. In fact, these groups have as good a claim as any to being impeccable Muslims.

On this site, it’s pretty uncontroversial to say the very same thing about Christian factions. In fact, we see this in the Friendly Atheist comments so often, it’s almost boilerplate: the rejection of someone’s assertion that “the guy who did [fill in an evil deed] isn’t a real Christian,” or that he doesn’t represent “true” Christianity.

If you agree that this “No True Scotsman” (or “No True Christian”) fallacy is logically illegitimate and a transparent blame-deflecting device, you’ll also call bullshit on the 100% similar “No True Muslim” fallacy, right? You’d have to concede Harris’s point, wouldn’t you?

Harris resumes:

This presents an enormous threat to civil society, which apologists for Islam and secular liberals can now be counted upon to obfuscate. A tsunami of stupidity and violence is breaking simultaneously on a hundred shores, and people like Karen Armstrong, Reza Aslan, Juan Cole, John Esposito, and Glenn Greenwald insist that it’s a beautiful day at the beach. Their determination that “moderate” Islam not be blamed for the acts of “extremists” causes them to deny that genuine (and theologically justifiable) religious beliefs can inspire psychologically normal people to commit horrific acts of violence.

Regular readers know I have no love for Christianity; I dislike all poppycock and superstition. But while the religious fervor of Christianity hasn’t precisely burned out (which is why it’s good to always keep a watchful eye on it), the fire is in its glowing-embers stage. After roughly a millennium and a half of crusades and inquisitions and indiscriminate heretic-killing, such appalling conflagrations have been robbed of oxygen by modernity and the Enlightenment.

By contrast, Islam today is where Christianity was some six hundred years ago. In large part, it’s a cauldron of blind zeal and bloodthirsty fanaticism. Of course, most Muslims don’t want to take part in the bloodshed. Many condemn it. All the same, hundreds of millions who may have no explicit hankering to slit a non-believer’s throat possess a remarkable degree of sympathy for those who performed the following handiwork (it’s an incomplete list, and not just because it only focuses on the past 20, 25 years):

Flew airliners into Manhattan office towers.

Blew up subway cars (and the innocent passengers in them) in London.

Bombed a night club in Bali (killing hundreds).

Created a huge bloodbath by setting off ten bombs aboard trains in Madrid.

Kidnapped and beheaded the journalist Daniel Pearl in Pakistan.

Laid siege to the heart of Mumbai with bombs and guns for three days, piling up the corpses.

Murdered hundreds of children and teachers in a school in Beslan, Russia.

Bombed the Paris metro.

Took and executed foreign hostages at an oil refinery in Algeria.

Attempted to detonate a car full of explosives in Times Square, New York.

Stabbed and shot several of Salman Rushdie’s translators and publishers in Italy, Norway, and Japan.

Set fire to a hotel in Turkey to protest Rushdie’s Satanic Verses, killing dozens.

Firebombed a British publishing house for publishing a historical novel about Mohammad.

Firebombed the Paris offices of the satirical magazine Charlie Hebdo for putting a cartoon of Mohammad on its cover.

Tried to blow up cargo planes and their crews in England and Dubai, with explosives packed in printer cartridges.

Shot and killed people on the Fort Hood military base.

Slaughtered the filmmaker and writer Theo van Gogh in Amsterdam.

Made multiple attempts on the lives of Scandinavian cartoonists who’d drawn pictures of Mohammad.

Shot and killed innocent people in the Washington DC area with a sniper rifle.

Tried to bring down a passenger plane with explosives hidden in the heel of a shoe.

Tried to bring down another passenger plane with an incendiary device hidden in the bomber’s underwear.

Shot little Jewish kids through the head in a schoolyard in Toulouse.

Tortured and killed upwards of 60 shoppers, including children, in a shopping mall in Kenya.

Indiscriminately killed and maimed bystanders and runners with bombs at the Boston marathon.

How do we know that hundreds of millions of Muslim support these atrocities? That’s a key fact from the major international Pew Research study that came out half a year ago. The PDF of the full report is here, but here’s one eye-popping finding:

The survey found the global median for Muslims opposed to violence in the name of Islam was 72 percent.

So a solid majority of Muslims do not openly engage in (nor openly support) killing for Allah. 72 percent! Terrific!

Except… well, what about the other 28 percent? There are roughly 1.3 billion Muslims on this planet. If 28 percent of them support violent jihad, that’s 364 million Muslims who condone, at least in some instances, the murder of apostates, blasphemers, gay people, cartoonists, loose women, and possibly everyone godless enough to attend a marathon.

In the United States, the picture is only marginally better. Eight out of ten U.S. Muslims say it’s not cool to strap a bomb to your chest and kill a bunch of kuffar. But nearly two out of ten say that’s dandy… at least in some instances. There are 2.6 million Muslims living in the U.S.… x 19 percent… yep, almost half a million American Muslims give suicide bombers and child-murderers-for-Allah two big thumbs up when they feel the violence is somehow justified.

Is there any other religious group that can “boast” this kind of enthusiasm for grotesque and appalling slaughter? Me, I’m not the slightest bit worried that scores of scheming Christians, Jews, or Buddhists are going to want to blow marathon spectators to smithereens, or butcher atheists and gay people, or fly Boeings into skyscrapers.

Harris writes that

The fact that otherwise normal people can be infected by destructive religious beliefs is crucial to understand — because beliefs spread.

Beliefs spread. Outrageous and damaging and often fatal ones. I don’t know about you, but this, more than anything, is why I’m a “New Atheist” — and why I’m especially wary of Islam.

Harris deserves the last word here: