Since last Friday, I’ve been thinking about Facebook Safety Check—what it means as a technology, and what it means for our perception of terrorism in the world.

On its face, Safety Check is stunning. In the 24 hours after terror came to Paris, 4.1 million people around that city marked themselves “safe” on Facebook. In turn, 360 million people worldwide received a notification from the social network saying that some or all of their friends were okay. For users with many acquaintances or relatives in the French capital, the weekend became a trickle of alerts: This cousin was fine, that old roommate was unharmed, this old colleague wasn’t even in the city at the time.

One of the main traits of a disaster area—one of the ways we judge whether something is mid-emergency—is informational chaos. On the Media, WNYC’s press-criticism program, warns in its “breaking news consumer’s handbook” that “in the immediate aftermath, news outlets will get it wrong.” But everyone gets it wrong. Getting it wrong, being unable to see the full picture, is part of the nature of zones of violence and destruction.

I think we discount how much the Internet has brought good sense to places where information was previously conflicting or chaotic. In the past few years, I’ve spent some time covering what’s come to be called “crisis mapping.” That’s where—using the Internet, software called Open Street Map, and donated satellite imagery—online volunteers map the destruction left over after an earthquake or a cyclone has wrecked havoc. This new data help rescuers and relief organizations know where to send food, shelter, and potable water. Crisis mapping is a miraculous service: Within hours, strangers bring coherence to an otherwise disordered place.

Safety Check has a similar miraculousness. To know, within an hour or two of an event, that someone is safe: It’s so valuable, so emotionally practical, as to be almost priceless. It is anti-terror, in a way: It says, be not afraid. And in the three places where it was first deployed—Afghanistan, Chile, and Nepal, all three after major earthquakes—its activation made a lot of sense, because earthquakes are events which by their nature can affect millions over huge swaths of territory.

But earthquakes and cyclones are not themselves public-facing events. Terrorist attacks are. As Brian Jenkins, a terrorism scholar at the RAND Corporation, writes, “terrorism is aimed at the people watching.” Terrorism is a public-relations campaign with guns and bombs. It weaponizes culture, and it exploits journalistic concern for heinous violence to grab media attention and get pathology taken instead as politics.

In other words, what terrorism seeks to create is a global shockwave of revulsion. It aims to make more people feel unsafe than were ever actually threatened. And it wants to use the media’s penchant for “following a story” to remind people over and over and over again about horrific violence, to the degree that the political group to which they belong—be it a city, state, or nation—starts doing very stupid, self-immolating things.

I find myself wondering whether Safety Check, when deployed during a terrorist attack, counters some of these impulses or ratifies them. On the one hand, maybe it’s the sole piece of information you need to know after a major attack: “The people you love are safe. You may pay attention to other horrors than these.” Or maybe it reinforces terror’s message, forcing you to look at the faces of friends who were never endangered in the first place, reminding you ceaselessly of the dozens of people who could have been in the wrong place, at the wrong time—but were not. It recreates the fearful shockwave that terrorism seeks to create.

Or maybe I’m overthinking this. Facebook, for its part, sees Safety Check as one more type of message. “Communication is critical in these moments both for people there and for their friends and families anxious for news,” says Anna White, a spokeswoman at the company. “People turn to Facebook to check on loved ones and get updates which is why we created Safety Check and why we activated it yesterday for people in Paris.”

I had emailed the company asking how it would activate the feature in future years, for more “human disasters,” as Mark Zuckerberg put it. How, I asked, would it determine which “human disasters” were major enough to warrant a Safety Check? (Would mass shootings here in the U.S. count?) Could we wind up with two levels of terror attack—those that generated a regional Check, and those that didn’t? Facebook did not reply to those questions.

But if the feature is deployed well, it could wind up being the most important kind of post-terror message. On Sunday, a friend with family in Nigeria remarked to me how useful she would find Safety Check if it were regularly deployed after Boko Haram attacks. The software’s message after that and terror elsewhere might be seen as simple but firm: “Your family and friends are safe. Mourn, but keep going.”