Now that we know a little about the brothers who appear to be responsible for the Charlie Hebdo attack—the children of Algerian immigrants, orphans, holders of low-wage jobs like delivering pizzas, attracted to jihad after what sounds like a typically aimless lower-class youth—we can start to think a little about what the shootings mean.

I appreciated Jon Stewart's earnest, humane response on Wednesday but I respectfully disagree that “there is no sense to be made of this.” People aren't earthquakes and lightning strikes. They do things for reasons. Even if they're misguided, brutal, and unreasonable reasons—they're still reasons.

And this attack is part of a pattern. There is sense to be made, even if it's a deeply uncomfortable sense.

Exhibit A: A response to the massacre by the masterful Joe Sacco that begins like this:

He goes on to test the limits of his freedom—drawing an African as a monkey with a banana, drawing a hook-nosed Jew counting money—and asks, "if you can take the 'Jew' joke now, would it have been as funny in 1933?"

Is there a difference between mocking Christianity and mocking Islam in a Christian-dominated continent with a xenophobic right wing that's on the rise? Is there a difference between Eddie Murphy putting on whiteface for Saturday Night Live in 1984 and Ned Haverly rubbing on some burnt cork for Yes, Sir, Mr. Bones in 1951?

Freedoms can be absolute but they don't exist in a vacuum. Of course cartoonists should be as free to mock a little old lady with bedsores living off welfare in a bedbug-infested apartment as they are to mock President François Hollande—and free to do so without the radical grannies or whoever spraying their workplace with bullets. But we don't live in a context-free universe. (If you haven't seen the 1995 movie La Haine—"The Hate," about a day in the life of a Jewish kid, an African French kid and an Arab Maghrebi kid who are friends and live in Paris housing projects—now is a good time.)

Which brings us to exhibit B, Ian Buruma, whose 2006 book Murder in Amsterdam, about a radical Muslim who murdered Theo Van Gogh for making a film that insulted Islam, is a peace-and-democracy-loving-but-still-nuanced look at the limits of tolerance in the Netherlands.

Among other things, he finds that the serious social friction doesn't start so much with the immigrants—who, he says, typically come to Europe to work hard, save money, and try to send their children to college—but with their kids. In my review of the book, I wrote:

The children are materially better off than they would be in their home countries, but buckle under the humiliation of living with a contemptuous native population while being dependent on their welfare state, "a society from which a young Moroccan male might find it easier to receive subsidies than respect." They are at home nowhere—not in the old country, not in the new country. Some plow through, finish their degrees, and enter the mainstream. Some give up and become small-time thugs. Some find comfort in a creed that justifies their rage and frustration and become Europe-hating Islamists. A surprising number lose their minds. As Buruma learns from a Dutch doctor, beaten-down first-generation Moroccans tend to suffer from depression, but "a young Moroccan male of the second generation was ten times more likely to be schizophrenic than a native Dutchman from a similar economic background."

Even in the freest of societies, some people are freer than others. The deck is stacked in their favor economically, psychologically, and institutionally. Theoretically, the Charlie Hebdo cartoonists and pizza delivery-drivers in the suburbs are equally free to do and say as they please (within the bounds of the law), but that's not how the world actually works.

Still, even the most sophomoric racist doesn't deserve to be massacred at school or at work or at the supermarket. What the killers did was a vicious attack on freedom of expression. As we saw with The Interview, sometimes the greatest tests of freedom come in vehicles that are pretty shitty in terms of artistic merit—Hustler, 2 Live Crew—which is what makes them such good tests. Even low-quality speech should be protected.

Buruma was a friend of Van Gogh's, admires his former partner in defamation Ayaan Hirsi Ali, and is an advocate for sex, drugs, and democracy. But he refuses to be simplistic about European-style freedom: "Perhaps Western civilization, with the Amsterdam red-light district as its fetid symbol, does have something to answer for... What happened in this small corner of northwestern Europe could happen anywhere, as long as young men and women feel that death is their only way home."

To say "there is no sense to be made" isn't just wrong—it's dangerously wrong. We have a problem here. And it keeps happening.