Just days after I interviewed the legal scholar Rosa Brooks about her book on her time as a civilian advisor in President Barack Obama’s Pentagon, the United States bombed Libya again. This was the third such strike in the U.S. campaign against ISIS there, but this time, Reuters reported, U.S. officials said it “marked the start of a sustained air campaign.”

Still, it was hard to tell how much of a turning point it really was. Small numbers of American special-operations forces have been active in the country since late last year, ostensibly to support local partners against ISIS, though details are vague. By launching more airstrikes at the beginning of August, America was not so much opening up a new front in its war on the group as maintaining an existing one. And it wasn’t so much changing tactics as amplifying them. Did this mean that the United States somehow became more “at war” in Libya last week than it had been the week before? For that matter, as U.S. planes have accelerated their bombing campaign against militants in Afghanistan this summer, and President  Obama has vowed to leave some 8,000 troops there through the end of his term, is the United States any less “at war” there than when U.S. combat operations in the country officially ended in December 2014? What about  in Pakistan, Somalia, and Yemen, where U.S. drones have killed thousands of people outside of what the government considers “areas of active hostilities”?

Brooks’s new book, How Everything Became War and the Military Became Everything, is about the limits of categories like these, just as much as it’s about war and the American military. Brooks, a writer and law professor at Georgetown University, bases her account in part on her two-plus years at the Defense Department, where she observed the blurring of the line, in her words, “between war and not-war.” The Pentagon, she writes, is on the one hand a “vast, bureaucratic, death-dealing enterprise;” on the other, the U.S. military operates in “nearly every country on earth” and in many cases its activities have nothing to do with shooting at bad guys. Its personnel, she notes, have been involved in everything from Ebola response in Liberia to agricultural reform in Afghanistan to health care in Malaysia. The range of their work is as remarkable as it is unsettling. If the U.S. military’s job is to protect America’s own security, why is it doing all of these things?

Brooks contends that the amorphous nature of modern security threats—conflict and terrorism, but also things like climate change and financial collapse—have made it “increasingly difficult to define a uniquely ‘military’ role and mission.” It’s not just that the Bush and Obama administrations’ pursuit of terrorists around the world have pushed the geographic boundaries of the so-called war on terror beyond the more formal battlefields of Afghanistan and Iraq. It’s also that, as the military has sucked up an increasing share of America’s foreign-policy resources in the post-9/11 era, the Pentagon has become “like a Super Walmart with everything under one roof,” as retired General David Barno tells Brooks. “Like Walmart,” she writes, “the military can marshal vast resources and exploit economies of scale in ways impossible for mom-and-pop operations. And like Walmart, the tempting one-stop-shopping convenience it offers has a devastating effect on smaller, more traditional enterprises—in this case, the State Department and other civilian foreign policy agencies.”

I spoke to Brooks recently about war, peace, and the space in between. What follows is a condensed and edited transcript of our conversation.

Kathy Gilsinan: The lines between “war and non-war are growing indistinct,” as you say. As a very basic question, what is war? And do you know it when you see it?

Rosa Brooks: I think we have absolutely no idea what war is. I think everything that frightens us, we now label war, more or less. And that’s a problem. As an analytic category, [war] has lost any clarity it might once have had.

Gilsinan: Are there any common features to things that are war-like?

Brooks: They run the gamut, and they have fewer and fewer common features. We look at Syria and we say, “Oh look, there’s war.” And that’s the sort of traditional understanding of war. Lots of people who are shooting each other, blowing each other up, generally killing each other.

But we also are thinking of cyber [operations], more and more, primarily through the framework of war. We look at terrorism through the framework of war. Already some of our thinking about what we call “illicit transnational actors”—not terrorists, but groups like narco-smugglers and traffickers—[is] beginning to get framed as part of war and war-like stuff.

When we think of sort of the classic understanding of war that we’ve had in Western society, it owes a huge amount to [Carl von] Clausewitz, the 19th-century Prussian military strategist whose very famous definition of war was: “War is the continuation of politics by other means.” But Clausewitz was really clear what those “other means” had to include, and Clausewitz’s understanding of war was that it had several defining facts that differentiated it from other kinds of competitions or conflicts that weren’t war. So, to Clausewitz, war is organized, it’s violent, it’s on a mass scale—not an individual scale—and it is for the pursuit of political ends. For Clausewitz, a game of chess is not war, because it’s individual, not violent, and it has no political ends. A rugby match where people end up with bloody noses and broken arms is not war, because although it’s organized, it also has no political ends. A barroom brawl is not war, because it’s not organized, and it has no political ends. Economic competition between states, however fierce, is not war, because it’s not bloody—it’s mass, it’s organized, and political—but it’s not violent.

In the terms of Clausewitz, where you have mass armies of thousands and thousands of people, and single battles that are killing tens of thousands of people, terrorism is small potatoes. But increasingly, we’ve got these things that, they’re not mass, they may not be organized, the political ends are sometimes unclear, and yet we’re calling them war. It’s not completely crazy that we want to, since we now live in a world where technology has enabled both states and even individuals to cause a level of disruption that it might once, 100 years ago, have taken war to achieve. So on some level, why not call it war if it sort of does what war does? On the other hand, Clausewitz would not have recognized [it], if you said “We’re at war with terrorism.” He would have just said, “Whatever you’re doing is not war.”

Gilsinan: I see how terrorists aren’t, under the Clausewitzian definition, doing acts of war on the United States, but the United States’s “war on terror” is organized, violent, on a mass scale, and for the pursuit of—

Brooks: We’re certainly responding with something that looks more like war. It’s just not all that clear that it’s entirely reciprocal. Could you have a war if only one party knows it’s a war? I don’t know how that fits into the Clausewitzian framework.

Gilsinan: Do you have in mind a glory era in which the lines were totally clear—[an American] war started when Congress declared it and ended with a signed peace agreement between the combatants? Or are there ways in which we’ve seen this continuum, rather than binary, between war and not war? There was never a peace agreement when the fighting stopped after the Korean War in 1953.

Brooks: The line between war and not war has never been as clear as international lawyers sometimes like to pretend it is—that we have this nice, neat framework that says wars have beginnings and ends; there are places that are at war; there are places that are neutral. There are combatants; there are civilians. You can kill the combatants, you can’t kill the civilians, end of story. And it’s never been that neat, obviously. On the margins at least, there have always been actors who didn’t quite fit—partisans, guerrillas, countries that were technically not at war but where there was a lot of proxy war activity going on. The categories were never perfect; they were always somewhat arbitrary. But now the exceptions have kind of overwhelmed the rule.

Gilsinan: “Now” being in the post-September 11th era?

Brooks: Very much so. September 11th itself didn’t create this world, but it’s both the symbolic beginning and a dramatic acceleration of a lot of trends that had been out there already.

Gilsinan: Which is interesting, because that era, in terms of the U.S. response, was kicked off with the more classic, interstate wars. You invaded Afghanistan, you invaded Iraq.

Brooks: Absolutely. And it was in some ways an illustration of our difficulty in thinking beyond the framework of traditional state-on-state conflict. Like there we were, confronted by something very different—an attack that didn’t involve traditional weapons, by a non-army, from multiple different nationalities. But the only thing we could figure out how to do to respond was go and invade a bunch of states.

Gilsinan: Then it sounds like the categories weren’t necessarily a good thing.

Brooks: They certainly limited our imagination, but I don’t know if I’d characterize it quite that way, because we had a choice. It was not inevitable that the 9/11 attacks would be categorized as starting a war in a legal sense. They could have been categorized as crime, they could have been categorized as in between—it’s not quite a war, not quite a crime, [so] we’re going to do some stuff that’s in between. It was not that there were no alternative categories available, it was that the Bush administration was not interested in using them. And I am not sure of the extent to which they themselves thought through the long-term implications of choosing to call it war—I think some did, some didn’t—but they sent us down one path, when other paths were available.

Gilsinan: When you went in [to the Pentagon] versus when you came out, what would you say was the biggest difference in your thinking about what war means?

Brooks: I was both impressed and somewhat terrified by the dawning awareness that the Pentagon does everything. If you go in with a bit of a stereotype of, the military shoots guns and blows stuff up, and then you find yourself in meetings with military officials who are talking about running a program to prevent sexual violence in the Congo, and doing a big research project on how you most effectively dissuade foreign militaries from using sexual violence during conflict, and then you walk into another meeting and people are talking about how to promote micro-enterprise among Afghan women, it’s both kind of amazing and inspiring—that there’s this unbelievably diverse set of talents and people [and] projects. It’s amazing that the U.S. can still marshal so much talent and idealism. At the same time, it’s kind of scary, because you think, “Wait, whoa, is this the right place? Do we know what we’re doing? And what happens to the military as an institution when we’re asking it and expecting it to be all things to all people?”

Gilsinan: What does happen?

Brooks: Well, we’ll find out. It’s a big experiment, and I think there are several possibilities. There’s a bad for the military, bad for the world possibility, and here’s what that one looks like: The U.S. military does everything, but it’s doing a lot of stuff that people weren’t trained to do, does it badly, that has bad effects on the lives of human beings all over the world. It also decreases U.S. credibility, because what the world sees as the face of the U.S. is the military. It’s a uniformed figure, which has bad ramifications for civil-military relations worldwide and for democracy. Meanwhile, the military as an institution is demoralized and less effective because we’re trying to force one institution to do too many things.

[There is a] more interesting possibility. All these categories we’ve been talking about—war, peace, conflict, combatant, military—we made them up. They didn’t come down from a divine power. This invites us to radically rethink what it is we want from our institutions, and how to organize them. And if the military is not doing these things well, but we think the United States needs to do them, and if we think it’s not realistic that the State Department or USAID starts doing them again or doing them well, it invites us to say, why shouldn’t we have a radically different military that combines within it a whole spectrum of activities, from traditional war-fighting to things that we think of as more peace-building and development? Why not really change how we think of the military, and change how we recruit, change our training, to make this an institution that does those things, does them well, and does them accountably? And that would be really hard. I think most people both in the military and outside of it sort of recoil at that and tend to want to go back to the much simpler “Well, shouldn’t the military just fight?” I don’t know if that’s even possible anymore.

Gilsinan: [We’re discussing] the dangers of this blurring of the line between war and not war. And yet there are fewer people dying in wars now than in the World War II era, when the boundaries were pretty clear, even if not completely clear. So on the one hand, the U.S. military is in maybe more countries than ever before, almost every country on earth. On the other, the worldwide level of killing going on is substantially lower than [at] almost any time in history. If the long-term trend is in this positive direction, how much should we worry about the categories?

Brooks: I think those are separate questions. I don’t think they necessarily have a whole lot to do with each other. But I also would question whether we have a long-term trend. In the sweep of human history, 50 or 60 years is not a long-term trend, and I do worry about that. Of course it’s good that we, over the last few decades, have seen a reduction in the number of people dying in violent conflict around the globe, but on the other hand, the world we live in remains extraordinarily dangerous in many, many ways, including some quite new ways, driven by technology—the speed at which epidemics can move around the world has increased due to changes in transportation technologies, the speed at which economic disruption can move around the globe because of changes in electronic technologies, et cetera. And, by the way, there are very many thousands of nuclear warheads and old-fashioned sources of destruction.

So I’m not all that comfortable when people say, “Oh, happy, happy news, interstate conflict and death have dropped in the last few decades.” There have been plenty of other decades in world history where you’ve gotten a few decades, a hundred years, or a few hundred years of relative cessation in violence, only to have new catastrophes. I am very, very skeptical of claims that what we have is a long-term trend, as opposed to saying we have no idea whether this continues or not, and lots of things could destabilize it.

Gilsinan: One of the things that could destabilize it is the expansion of the U.S. military all over the world and the tendency to view everything that scares us, as you say, in terms of war.

Brooks: When you build up a national and international legal system where our ability to constrain power and coercion are very much linked to the creation of this particular set of legal and political categories—armed conflict, foreign, domestic, military, civilian—then when those categories get blurry, you lose your ability to effectively constrain power. But that’s not the same thing as saying the answer is necessarily to shore up the categories again. The categories themselves are arbitrary—what’s important is their relationship to a much broader system of consensus, of institutions, of laws, and so forth. We didn’t create these categories because there’s something magical about [them], we created these categories because they were part of a system that helped us achieve certain normative goals that have to do with the rule of law, with promoting stability and peace and so forth, and if the categories aren’t doing it, then maybe the categories don’t make sense anymore. Maybe we now live in a world in which we need an in-between category, something that’s in between war and peace, with a set of in-between implications for law and for power and for rights.

Gilsinan: Are those categories Western-invented? To what extent is, say, Russia observing those categories? To what extent is China?

Brooks: Every culture in the world has had some concept of war and some notion of what should be permissible and what should be prohibited during wartime, and what the distinctions are between warriors and non-warriors. In that sense, there’s nothing Western about it. In a narrower sense, sure they’re Western—the Geneva Conventions [are] what we think of the modern law of armed conflict, [and they] very much arose out of conflicts between Western states in the 19th century and the first half of the 20th century. I think Russia and China—partly because they’re authoritarian, which gives them the ability to move a little more rapidly because they don’t have to worry about debate or argument, and they’re less scrupulous, frankly—have been much more quick than Western states to look at the issues we’ve been talking about and say, “These categories don’t make any sense anymore, and that is an opportunity for us. We can exploit the West’s continuing insistence that the categories do make sense while we do whatever we want.”

Gilsinan: The “little green men” and turning off the electricity in Ukraine.

Brooks: Absolutely, the Russians have been very creative about operating in that space between war and peace in ways that have been very hard for the West to respond to, in part because they sort of confound our categories. We want to look and say, is there a war? Or is there not a war? And the answer is, well, hard to say.

Gilsinan: And that opens up space—potentially dangerous space—because I think some of what constrains American policymakers is saying “Look, do we really want to start a war with Russia over Crimea?” But if there’s some in-between option, of combating Russia in Crimea or contesting the annexation of Crimea, without resorting to war but resorting to some sort of in-between category—do you see that happening already?

Brooks: Not very much. I think that particularly in the special-operations community within the military, [there are] conversations about [how] we’re probably permanently in some kind of gray area between war and peace. Our adversaries are operating with comfort and creativity in that world. How do we operate in that world? I think the question is, if we’re going to be operating in that world, how do we do so while preserving our commitment to rule of law and democracy?

Gilsinan: The drone war is one of these issues where you could say it represents an in-between category—we’re not at war with Pakistan, we’re not at war with Somalia. There’s a long history of soldiers trying to kill at a distance, stretching back to the ages of throwing spears and longbows and up through the age of cruise missiles. And you mention that you’re troubled by the innovation of drones but that you had trouble articulating what it is about drones in particular that was disturbing. Can you try to articulate it?

Brooks: The drone war both highlights what is promising and what is frightening about some U.S. efforts to kind of operate in that in-between space. Start with the promising part: Yes, of course, we’ve always tried to find ways to kill the bad guys from a distance without risking the lives of our people. It’s not a bad thing to want to do that. It’s a good thing. Nobody thinks our troops should be engaging in hand-to-hand combat with terrorists because it’s more chivalrous or something. And also the drone strikes represent part of a trend towards the individualization of warfare, where instead of firebombing Tokyo or Dresden, which kills thousands upon thousands of people from soldiers to infants indiscriminately, we now have a technology that enables us, combined with our intelligence and surveillance resources, to be really focused in who we target and say, we’re not going to drop a bomb on cities in Syria, we’re going to bomb this guy over here. And we are pretty amazingly good at hitting that guy and nobody else—not always, no question. And I sometimes say to my friends who say “I don’t like targeted killing,” “Would you prefer untargeted killing?” Because that’s what World War II was most of the time, with catastrophic results for civilian populations.

But here’s the dark side: Because it’s individualized, because it operates below the radar and it’s a technology that enables covert use of force across borders, it becomes invisible and shielded from meaningful democratic accountability, and shielded to some extent from international laws because of the deniability. This is our way of exploiting categories. The Russians use the little green men, when we use covert targeted strikes by unmanned vehicles. We then get to say, “Hey, this is just lawful wartime targeting combatants, there’s nothing new here, so leave us alone.” And yet at the same time, normally in a traditional war you know who the enemy is, you know where the battle is, and we don’t know any of those things. The claims the U.S. makes about these targeted strikes are completely non-falsifiable because they’re really not saying anything, and what little they say says, “Well, we can’t tell you who we targeted, we can’t tell you why, it’s a secret, trust us.” And that’s very, very frightening.