Rukmini Callimachi is arguably the best reporter on the most impor­tant beat in the world. As a New York Times correspondent covering terrorism, her work explores not just what jihadists do but how they do it*. *You’ve read her stories on ISIS’s use of birth control to maintain its supply of sex slaves, or the Kouachi brothers’ path to the Charlie Hebdo attacks in Paris, or the nature of lone-wolf attacks like the recent mass shooting in Orlando. Her byline often appears on the front page of the paper; at just 43, she’s received three Pulitzer Prize nominations. Perhaps the most remarkable thing about Callimachi, though, is how she gets her insights into the world’s most hostile and secretive organizations. Sure, she spends months every year out of the country reporting, but increasingly her work requires just as much time staring at her phone and computer screen. Social media enables Callimachi to access what she calls the “inner world of jihadists”; she lurks in Telegram chat rooms, navigates an endless flood of tips on Twitter, and carefully tracks sources and subjects all over the Internet. Her cell phone battery dies up to four times a day. The truth, she has found, is as much online as it is on the ground.

Wired: How did you start covering terrorism?

Callimachi: In December 2006, I became the West Africa correspondent for the Associated Press. As it happened, that was the year that a group there pledged allegiance to al Qaeda and became their North African branch. Very quickly, large swaths of their area were deemed too dangerous for a Westerner to visit, and I saw my own world shrink as a result.

Then in 2012 they succeeded in taking over northern Mali. The area that they controlled with two other groups was enormous, the size of Afghanistan. They imposed Sharia law, cut off people’s hands. An adulterous couple was stoned to death, and women had to be veiled. It was one of the biggest stories on my beat, but it was frustrating because I couldn’t go there, so I was covering it by phone. Then in 2013 the French went in to push back the jihadis, and suddenly reporters were able to go in behind them.

Was there a massive influx of press?

Other than Hurricane Katrina, I don’t think I’ve ever seen so many journalists as I did then in Timbuktu. We were all traipsing around the city doing similar stories, so I started asking the local people if they could show me the buildings where the group had been. They took me first to a bank that had acted as the Islamic police center, and they took me to a hotel that had been turned into a Sharia court, and they took me to a tax building that had been the jihadists’ administrative office. In each of these buildings, I noticed dozens and dozens of loose papers on the ground that were written in Arabic—even though Mali is largely a French-speaking country. Because I couldn’t read them, I didn’t think they were very important. The next day, I realized, “Oh my God, that must be the stuff the jihadists left behind.” So I went back with a bunch of trash bags, and I just went building by building, at least 10 in all, and scooped up every single thing that I could find. People were calling me the trash lady of Timbuktu. I started to translate the documents in my hotel with a translator.

I had wrongly assumed that these were just a bunch of guys in a cave in a desert, very primitive and wedded to an ideology for no good reason. But in the documents I saw something much more nuanced: There was everything from ideological debates on aspects of theology to expense reports.

What did all of that tell you?

I realized that this was a much more complex movement than I had thought and that the way I had gone about reporting on it—talking to officials, trying to talk to intelligence people—was not the most interesting approach. The group itself provides so much raw material that if you start digging you’ll find an enormously rich source of stories and reporting targets.

Your reporting completely changed my understanding of these groups. Until I read your work, I couldn’t see them with any nuance.

When I was publishing those stories in 2013, there was so much pushback on me from editors and then from readers. The critique was, “How dare you give these people a voice? How dare you see them as anything other than the disgusting dogs they are?” The thing is, my reporting doesn’t deny that they’re perpetrating crimes against humanity, but I think that our job as journalists is to understand and to bring gray where there is only black and white. Because there’s always gray.

How is this beat different from others?

If you’re doing a story about a shooting in America where lots of people died, you would without fail call the lawyer of that crazy person to get the criminal’s response. You might not give it much consideration, but at least you’d get their “no comment.” This is the one group where we don’t even try. I had to wrestle with a lot of criticism for reaching out to them and trying to speak with them. The criticism is that by reaching out, I’m giving them a mouthpiece for their propaganda.

Isn’t that a real risk?

I’m always wrestling with it. But the approach where we don’t listen to their side at all is, in my opinion, why so many people, so many officials, missed the rise of ISIS. They put something out and we said, “No, no, no, we’re not going to listen; it’s propaganda.” As somebody who’s been listening to them since 2012, it was really clear to me that ISIS was the next big thing. And I argued with people over this. The first indication to me was when the French broke up al Qaeda in northern Mali and those jihadists scattered into the desert. The few that I was still in touch with started telling me stories about their “brothers” leaving Mali and going to Syria to join ISIS. That was a red flag for me, because the natural thing would have been for them to join the Nusra Front, which is the al Qaeda affiliate in Syria—but instead they were choosing a group that was openly in conflict with it. To these young men, there was something so exciting about ISIS and the caliphate project that I just saw the ranks of al Qaeda being drained by this new group.

How were you listening to these jihadists?

Well, I was trying to talk to them, I was reading their propaganda as it was coming out, and I was watching their activity on social media.

Isn’t that what our government should be doing?

Look, when I found those documents in Mali, the last Obama election had just happened and so had the killing of Osama bin Laden, which was obviously a very big deal. What was coming out of Washington was that we had decapitated the snake, that without top-down control, al Qaeda is in disarray. Like everybody else, I bought it. I wrote a bunch of stories that essentially rephrase that line, because that’s what officials who seemed well informed were telling me. But in Mali I realized how wrong they were, because I’m sitting there holding letters from the general manager of al Qaeda to some dude in Mali—letters that were couriered across the desert, across the ocean from Yemen. And this is an organization that has no control over its affiliates?

They have expense reports!

That was when I went, “Oh my God, I’ve been taking what the government says at face value.” Because this is such a difficult beat, you often don’t have anywhere else to turn. Somebody at the US embassy or the NSA tells you something; they never share with you how they know what they know, but they sound sure of themselves, and where are you going to go to disprove that? But finally I had real information, and I started to realize that there’s a politicization to intelligence.

The administration’s narrative was that they had defeated this terrorist group. The Obama administration had killed bin Laden, but the analysis was wrong. Al Qaeda had created a structure that was meant to regenerate itself and no longer be dependent on just one person. And that’s exactly what happened. The ideology is now a living, breathing thing, even more than it was at 9/11, because of Twitter and other modes of social media. You no longer have to go to some closed dark-web forum to see this stuff.

How do you find them online?

Back in 2012 and 2013 they were using these closed forums that were mostly in Arabic, and you would need a password to get in. The only way to try was to impersonate a jihadist, which is not within the ethics of my profession—not to mention that I don’t speak Arabic. So at that point I relied on what they said publicly, though I was speaking directly with one senior al Qaeda member.

They’re smart enough to know the reporters who are covering this beat, so when journalist James Foley was executed by ISIS, they tweeted the video directly at me. It was awful. As Twitter has become more aggressive in shutting them down, they’ve migrated to Telegram, which is basically an encrypted app where they create a channel, like a little chat room. You have to know the exact address to be invited, and the address is complete gibberish. With Twitter you can guess; you look for certain words and you end up finding these accounts. And then it’s kind of organic: You go to one account, then you go to their followers and you follow all those people, and suddenly you’re in the know. Telegram is much harder.

How do you figure out the crazy Telegram addresses?

You have to be speaking to someone who is a jihadist. The real hardcore ISIS members don’t talk to reporters like me unless it’s to insult us. But there are always people on the fringes of these groups who have one foot in. I think I’ve only ever quoted one or two jihadists, because I could verify who they were, but the vast majority are basically just tips. I spend an enormous amount of time chatting with them, but I can’t say with certainty who the person is, so I can’t quote them. So I stay in touch with these people who are on the fringes, and they share a couple of these Telegram groups with me, and once I get into one, they’ll post the link to another one, then a third, then a fourth. These Telegram channels are being shut down just like the Twitter accounts, so they’re now actively putting up backup channels. They’ll say “Brothers and sisters, please follow us on these backup channels.” It feels like a Sisyphean task every morning when I have to go onto Telegram on my commute to work. I’m sitting there on the bus, joining, joining, joining, and half the channels I was on the day before aren’t there anymore or are no longer good. But it’s no longer password-protected; I don’t have to lie to join.

What kind of username do you have?

I have a vapid name—I’m not going to tell you what it is—that makes clear I’m a journalist but doesn’t give my affiliation. With my own name I was constantly being blocked.

Do they use a lot of platforms?

It’s a very nimble group. In the past two years, they’ve been experimenting. Twitter is the main engine, but they’re also using Tumblr and Instagram, so they’ll have multiple tentacles to push stuff out. They’ve become so good at it, it’s unbelievable.

Do you wish the government and tech companies weren’t as good at shutting them down?

Twitter really needs to take them seriously because they’re not just talking to each other, to people who are already radicalized, they’re also fishing for people who are maybe interested and maybe not.

Can you give me an example?

There was the case of Alex, this young woman in Washington state—a Sunday school teacher who was as American as you can get. The found her on Twitter; within three months she had converted online and was flirting with the idea of marrying one of the fighters and moving to what they were calling a Muslim land, which was pretty clearly Syria.

How did you find out about her?

I will interact with pretty much anybody on Twitter, anybody who DMs me and is reasonably polite. I still don’t know the real name of the person who introduced us; he seems to be someone who spends an inordinate amount of time online and is a little crazy. He noticed Alex and messaged me, and within a couple of weeks I was at her house.

One of the all-time great tips. How did this guy notice her?

So you have all the ISIS people and all the sympathizers of jihadist groups, and on the other side you have the Anonymous group—and I’m using “Anonymous” very loosely. It’s a group of do-­gooders, some of whom are hackers, some of whom want to be hackers, and they’re in this online vigilante sphere: identifying ISIS accounts and flagging them to Twitter, trying to get them suspended. They follow the jihadists online very closely. Just like the ISIS guys, they’ll never tell me who they really are, so I’m not going to do a story on them, but they’re doing stuff that I can’t do. A lot of them are going undercover and pretending to be Muslim. They’ll have names that make you think they might be a jihadist, and as a result they’re finding stuff out in a space that I can’t occupy. They’ve turned out to be pretty helpful to me.

So how much are you on these digital platforms, reporting?

When we stop talking, I’ll have probably 37 or so notifications on my Telegram, God knows how many on Twitter and other platforms, and I’ll just go and start looking through them. Most of the time I don’t do anything with them, I’m just constantly storing this information in my mind so I have an understanding of what they’re talking about, what they’re messaging about right now. So, for instance, right now there’s a lot of stuff regarding spies; they’re beheading people left and right, and they’re always described as spies. Maybe they are spies, who knows. But it shows me that they don’t feel very safe in their current state.

There’s also an enormous amount of propaganda about air strikes. Every single thing that falls from the sky is called a coalition air strike. They’re messaging really heavily on that and trying to create a perception that the Brussels and Paris attacks were a reaction to aggression against them.

How close can you get to the jihadists geographically?

Obviously I can’t go to places that are ISIS-controlled, but I can go just outside them, like the areas of northern Iraq at the feet of the Sinjar Mountains, where you can speak to recent escapees. I also try hard to get to ISIS and jihadi strongholds right after they are liberated, as in Timbuktu in 2013. That’s when the terrain is most raw and you can get the most original reporting. I was in the city of Sinjar on the day it was freed from ISIS last November and in the province of Hasakah, Syria, on the day it was declared cleared by a rebel group.

Are you ever afraid for your life?

I don’t seek out danger. Although I’ve traveled to areas that have just been liberated, I always do it with preplanning and forethought. So I’ve rarely found myself in situations where there was a real threat to my well-being.

How did you find out that ISIS captors were forcing birth control on their Yazidi sex slaves?

When I was reporting on ISIS’s system of slavery in 2015, I contacted scholars to try to understand what the scriptural basis was for slavery. Professor Kecia Ali at Boston University asked me if the fighters were checking for pregnancy and explained that if they weren’t, they would be in violation of established principles in Sharia law. That question spawned a whole other reporting trip to northern Iraq to ask the women what happened if they became pregnant. It was then that I learned about the fact that many were given birth control.

Has the way you pitch stories to your editors changed at all?

I think my editors now just trust me, but when I first came to the paper a couple of years ago it was a bit of a hard sell to convince them that ISIS was a threat when our government was calling it the “JV team.”

Is Twitter a crucial tool for you to cover terrorism?

Now that I have like 90,000 Twitter followers, I’m no longer having semiprivate conversations with 18-year-old hotheads who think they’re into ISIS. But Twitter has become such an interesting medium, in the sense that I can use it to get out everything that ends up on the cutting-room floor, to kind of storify it in a series of tweets.

Do you ever shut it all out? Twitter, the noise, all of it?

What’s nice about Twitter is there’s a block button, and I’ve used it to great effect. I mean, I don’t know if they have a tally of how many ­people I’ve blocked, but I’ve blocked a lot of people. And it’s not just ISIS people, it’s the Tea Party. The strange ones come from all sides; you have people who hate Muslims who are just as aggressive as the ISIS folks.

How do you keep from getting overwhelmed by it all?

I’ve come to the point where I metabolize it pretty quickly. I love what I do, and I think my body understands at some level that I have to put some distance between myself and my work. My very first big story as a journalist was the earthquake in Gujarat, India, in 2001. I had never seen a natural disaster on that scale before. I had never seen people piled up dead, and I remember walking through the streets with tears streaming down my face. It was so intense and poignant and big. It’s never been like that again.

Caitlin Roper (@caitlinroper) is WIRED’s* articles editor.*

This article appears in the August issue.