As it dragged on over nearly two years, the Mueller investigation laid bare the inherent difficulties in thinking about or even identifying conspiracy thinking. Representatives of both sides—those who fervently wished the official inquiry would yield evidence of Donald Trump’s criminality and those who just as fervently hoped it would amount to nothing—charged their opponents with adopting a dangerously conspiratorial mind-set. This is also where the common ground ended. Trump’s antagonists insisted there was enough evidence to suspect a plot to collude with a foreign power during the 2016 election campaign or to obstruct justice afterward or both. The president’s allies, by contrast, fixed on the idea of a secret, albeit thwarted, scheme by the deep state or alternatively the Democrats to stage a coup and illegally reverse the mandate of the American people. The public, buffeted by these warring claims, was left to guess who (if anyone) was on the right track and who was simply spinning elaborate tales for political gain.

Mueller’s long-awaited report could have made a difference. Many people expected that it would clarify what happened and offer some answers about how to differentiate between fantastical speculations and sound explanations going forward. Alas, this proved to be more wishful thinking. Even after the redacted version of the report was finally released this past spring, it still seemed the truth was—as is often the case with charges of conspiracy—in the eye of the beholder. (The Jeffrey Epstein jailhouse suicide is only the latest such example.)

In their new book A Lot of People Are Saying, veteran political scientists Russell Muirhead and Nancy L. Rosenblum declare themselves here to help. On the subject of the Mueller inquiry, they are unequivocal. They insist the probe was a legitimate investigation by a team of legal fact finders backed by an official knowledge-gathering institution of just the sort that helps protect democracies from the dangers of conspiracy thinking as well as conspiracies themselves. It is exclusively the cynical cries of “witch hunt” and “hoax” by the president and his supporters, they continue, that should worry us.

But Muirhead and Rosenblum have a considerably more ambitious agenda than just setting that record straight. A Lot of People Are Saying is intended to be a reasonable person’s primer on conspiracy thinking in and for our time. The authors not only attempt to spell out how conspiracy-mindedness differs from the healthy skepticism and commitment to exposing abuses of power that democracy requires—a task that runs its own risks, they admit, since sometimes conspiracies turn out to be real. They also lay out a quasi-historical argument. As of late, they argue, traditional or “classic” conspiracy thinking has been replaced in the United States by a new form of what they call “conspiracism,” and this conspiracism, defined by its detachment from big arguments or concrete forms of evidence, is undermining our democracy in novel and alarming ways.

No doubt Muirhead and Rosenblum are right to be frightened. (Who isn’t?) Their brief if repetitive book offers us a very readable account of the identifying features and effects that distinguish older, healthier forms of conspiracy thinking from this newer, more dangerous, and for now, as they see it, largely American brand. What the reasonable reader might be left wondering, however, is twofold: How neatly can these lines ever be drawn? And how much are we misconstruing the present—not to mention the past—when we take the thinking of the Trump era to be historically sui generis? In the end, framing the book around such stark contrasts and ignoring evidence that might complicate this picture obscure the real and complex forces driving today’s boom in conspiracy-mindedness. It largely hides the fact that nothing about conspiracies or conspiracymongering—or, for that matter, conspiracy suppression—ever turns out to be as clear-cut as anyone, on any side, might wish.

Muirhead and Rosenblum pursue their prey primarily as theorists, and they remind us at the start that conspiracy claims, always and everywhere, are designed to draw attention to the nefarious actions of ill-intentioned people. According to conspiracy framers and believers alike, “malignant forces”—which our authors describe as typically synonymous with a powerful elite, but sometimes including more marginal groups in a society, such as recent immigrants and members of minority religious communities—spend their time trying to harm the well-being of the rest of us. Importantly, they do so in secret, from behind the scenes. Thus, for the conspiracy-minded, exposing these forces before they can do more harm becomes an urgent task.

And who can dispute that this is a recognizable pattern of thought? Muirhead and Rosenblum follow the lead of historians in showing how such arguments about ominous beneath-the-surface doings have been used on the right and the left with varying effects, including forging social bonds among those in the know and generating novel political movements. The authors open their first chapter with the old saw that the American republic was born in 1776 out of a largely legitimate conspiracy theory about British tyranny developed by rebellious colonists to justify a war of independence. The authors sign on, in passing, to the notion that this “paranoid style,” as historian Richard Hofstadter named it in 1964, has had an important, if not dominant, role in US political culture ever since. Occasional references to conspiracy claims punctuating American history, from the muckraking of the Progressives in the late 19th century to early 21st century underground efforts to determine what really happened on 9/11, are intended to help make that point.

Muirhead and Rosenblum’s real interest, however, is not in identifying universal patterns or recovering the American past. What they are primarily concerned with is the peculiar nature of conspiracy claims right now, in the age of the Mueller report. In their telling, the nature of these claims has over the last several years, at least in the United States, changed substantially and for the worse—a trend they blame rather generically on conservatives’ hostility to government, a rising antipathy to elites and other social resentments, political tribalism in our identity politics era, changes in technology, and not least, the current occupant of the White House. Their goal is to catalog what differentiates the exceptional and troubling “new conspiracism” of the Trump moment from the conspiracy theories ginned up in the wake of 9/11, not to mention in the distant past.

One significant change, they argue, has to do with standards of proof. Whereas in the past, conspiracy claims relied for support on grand theories and elaborate explanatory mechanisms, today they function largely without either. Similarly, while “classic” conspiracy thinking often rested on a hodgepodge of evidence, forensically chronicled as if by professional detectives, these days backing up such claims with data seems beside the point. Contemporary conspiracism, Muirhead and Rosenblum announce, depends almost entirely on simple assertions of wrongdoing: “Fake news!” or “Rigged!” or the titular “A lot of people are saying…,” endlessly repeated.

Muirhead and Rosenblum also argue that, in contrast to the past, conspiracy theories today do not exist in support of any readily identifiable ideology. Whereas the Progressives, for example, once pushed conspiracy theories about corporate monopolies and party bosses in an effort to strengthen participatory democracy, that kind of purpose has become obsolete. Charges of conspiracy are now purely negative or, in the authors’ words, “politically sterile” and are intended to lead nowhere in particular except down (though it is unclear why anti-governmentalism could not be called a political agenda of sorts). But this is not to say that such charges are embraced by people who have not taken a side. On the contrary, Muirhead and Rosenblum insist these new-style conspiracy claims have a strong and distinctive “partisan penumbra.” They are, at the moment, the exclusive province of the right, where antipathy to government and the political establishment is rife and, distinctively, have no precise counterpart on the left of the political spectrum.

Then there are the effects of the current conspiracism, which Muirhead and Rosenblum consider unprecedented and unprecedentedly threatening to the life of our democracy. We make a mistake, the authors warn, to see far-fetched conspiracy theories like Pizzagate and QAnon—not to mention charges of rigged elections, deep-state actors, and presidents without US birth certificates—as marginal nuisances. Not only are they now coming at us from the top, thanks to Trump; they are also fast undermining popular confidence in democracy by breeding a deep distrust in the efficacy and even basic goals of its critical institutions. This is especially the case when it comes to those institutions in the business of knowledge production, such as universities, the free press, and for that matter, the Office of Special Counsel in the Justice Department. Many citizens now see them as sources less of factual information than of yet more manipulation and spin. It is also the case when it comes to those institutions that help keep alive the key democratic principle of legitimate, loyal opposition. Muirhead and Rosenblum pay special attention to political parties, the study of which is their shared academic specialty, and the acute danger of parties losing their status in the American imagination in the wake of the new conspiracymongering.

And that’s not all. Muirhead and Rosenblum declare that today’s conspiracism threatens to eat away at our shared sense of the world—another vital ingredient of a healthy democracy. Conspiracy propagators blithely blur good and bad information, confusing the rest of us to the point that we don’t know what to believe anymore. As a result, we give up on what we hold in common, which the authors label “common sense,” and we retreat further and further into political tribalism and what they term “epistemic closure” but could be called closed-​mindedness too. The content of this common sense, which Muirhead and Rosenblum argue has been “defied,” “betrayed,” and “insulted” as of late, is never fully spelled out; one wonders at times if it isn’t more a term of persuasion than of substance, much like “conspiracism.” Surely, though, Muirhead and Rosenblum are right that this kind of epistemic closure, or turning away from any shared factual understanding of the world, can undermine our commitment to peaceable forms of disagreement and open the way to violence. We need only recall the denouement of the Pizzagate fable: the man who showed up at the Comet Ping Pong pizza place in Washington, DC, in 2016 looking to “self-​investigate” a child-sex ring supposedly operated by Hillary Clinton and the Democrats out of the basement and fired three shots with an assault rifle in the process.

Yet how much of this is really new? A Lot of People Are Saying aims to convince us of the novelty of the present. The book’s big argument is that we are dealing with a rather sudden departure from the kind of conspiracy thinking that has always been a part of American political life and we urgently need to identify the break in the pattern before we can start to dismantle it. However, once we get into the weeds, the authors’ Classic Coke–versus–New Coke model doesn’t really hold up all that well.

Take the recent resurgence of anti-​Semitism not just in the United States but around the world. Muirhead and Rosenblum mention the scapegoating of Jews, but only in passing. Yet the newish obsession with one man, George Soros, that now situates him behind every scary twist in global politics, from an assault on Christian European culture in Hungary to the arrival of caravans of the dispossessed at the southern border of the United States—an idea floated from Twitter to the House of Representatives—is really just a twist on one of the oldest conspiracy theories around. Insofar as the new Soros-obsessed propaganda reinforces the idea of wealthy, cosmopolitan Jews as puppet masters secretly plotting to dominate the world through its key institutions, it is hard to see much that is innovative here. Anti-Semitism has always served as a locus for misdirected feelings of anger and alienation and been largely immune to facts or logic. Here in 2019, that still seems to be very much the case.

But looking back at the supposed “classic” tradition of American conspiracy theories that Muirhead and Rosenblum sketch based on the now slightly dated scholarship of Bernard Bailyn, David Brion Davis, and Gordon Wood, one cannot help noticing that a lot of what passed for politics in the early American republic was hardly the high-minded conspiracism of the authors of the Declaration of Independence, either. Late 18th century American newspapers, as partisan and commercially motivated as any Fox News show, were rife with invective and naked assertion along the lines of “Rigged!” and regularly eschewed evidence-based arguments. Open any page of, say, a Philadelphia newspaper of the 1790s and what do you get? The doctor turned political leader Benjamin Rush is a murderer, determined to kill yellow-fever victims with his bloodletting methods. The so-called New England Illuminati are, with their secret papal loyalties, attempting to undermine religious and political freedom and bring back absolutism of the clerical and monarchical variety. At the turn of the century, John Adams accused the entire opposition press of being nothing but a bunch of “foreign liars.” Even Tom Paine was a purveyor as much of conspiracy theories as he was of anything like “common sense.” Only the alleged conspirators seem to change, encompassing at different historical moments Mormons, anarchists, Catholics, Wall Street tycoons, and yes, government agents and political figures.

As for the claim that today’s conspiracism doesn’t stand for anything beyond negativity, isn’t MAGA itself a racial and class fantasy about a lost American golden age that can be restored only by draining an ill-defined “swamp”? That is more than just anti-government nihilism. And even if no one is organizing a nationwide citizen army under its banner, isn’t all the talk about potential violence just that—a call to action, when needed, in defense of this vision of the United States?

Muirhead and Rosenblum offer us some keen insights into the nature of conspiracy claims today, but their lines of demarcation—including the ones between conspiracy thinking and acceptable skepticism and between conspiracy thinking and common sense, not to mention between the “classic” and “new” varieties—seem not nearly as self-evident in practice as they are in theory. Nor do they seem as resolutely American, given the role that conspiracism is playing in mainstream politics right now all over the globe, from the United Kingdom to India to Brazil.

Perhaps what’s really different at the moment, then, is not so much the form that conspiracy theories take as simply the extent of their reach in the age of the Internet and Silicon Valley—and consequently how fully they have managed to infiltrate our entertainment and information culture, blurring where politics begins and ends.

We learn something about how this happens in A Lot of People Are Saying. Using the example of QAnon, a hoax that started with a single anonymous online poster called Q, Muirhead and Rosenblum helpfully demonstrate how conspiracy theories travel across the Web and beyond. They describe this particularly nutty story migrating and morphing from 4chan and 8chan message boards, where the conspiracy-minded collect and interpret clues as a leisure-time activity (which seems to work against the idea that all is now done with innuendo and assertion), to viral YouTube videos to celebrity endorsements and national press coverage, sweeping up new believers and, one suspects, those just looking to be entertained as well.

Yet Muirhead and Rosenblum pay almost no attention to the often invisible structural support systems that enable such preposterous tales to go viral. There is little in A Lot of People Are Saying about the technologies that make the Internet, especially its message boards and social media platforms, such a fertile home for conspiracy theories in the first place. We learn almost nothing, for example, about how many of their basic design features—authorial anonymity, the algorithms that control what audiences see and when, and a seeming ability to transcend time and space—aid in the transmission and influence of so-called conspiracism, as opposed to verifiable truths, today.

Muirhead and Rosenblum say even less about the economics of conspiracy theory, in which false narratives can be big business, whether for individual YouTube stars peddling hoaxes or the major Silicon Valley companies themselves, or about the national and international legal frameworks that make possible this state of affairs. The authors might well counter that their interest is more definitional, that they are in the business of delineating types of conspiracism, not exploring its causes. But the substance of today’s claims may be the least innovative part of the phenomenon. New technologies, along with the financial systems and the laws that sustain them, are what really allow recurrent, even atavistic rumors and conspiracy theories, like those about child abductors or corrupt political operatives, to spread today with a speed, scale, and impact that would have been impossible in an earlier era.

And in the end, A Lot of People Are Saying offers scant empirical research of any kind to support its core arguments. Yes, Muirhead and Rosenblum bring up a few real-world cases of conspiracy thinking widely reported in the mainstream press and provide the occasional historical example or footnoted quote. Nevertheless, they come close at times to relying on the kinds of assertions, unencumbered by evidence, that they reject in theory. Or to put it another way, readers would likely have benefited from a little more traditional conspiracy-minded thinking, in the sense of deep detective work and connecting the dots, on the part of the authors.

Muirhead and Rosenblum differentiate, for example, between the phony climate-science information pushed by corporations like Exxon and their Republican defenders, on the one hand, and the full-on, Internet-fueled denials of climate science as a hoax, on the other. The latter, they say, are more insidious and harder to refute. But what they don’t tell us is that the sources for these two strategies turn out in some cases to be financially and institutionally linked, as enterprising journalists have started to show. The same with the Soros memes all over the globe that seem to come from the bottom up but can be traced back to DC political consultancies and Rupert Murdoch’s Fox News. Such findings make it much more difficult to offer answers as to who is engaging in what kinds of conspiracism and toward what ends. The authors remind us that we don’t want to take much at face value, especially now. We need to know what is happening behind the curtain, because the world is, in fact, rigged by the powerful in all sorts of ways.

This disinclination to stray much below the surface carries over when, finally, we get to solutions. The authors’ arguments for how to combat the new conspiracism, which take up the last third of the book, are fine as far as they go. They are liberal staples. Speak truth in the face of conspiracymongering even if it will frequently backfire, as the authors admit it will. Shore up democratic institutions, including political parties, so they can once again organize our political lives. Encourage political leaders, even when there is little professional incentive for them to do so, to step at least temporarily outside the “partisan penumbra” to dispute obvious falsehoods and far-fetched tales.

By themselves, though, these suggestions amount to pretty weak tea. Muirhead and Rosenblum say nothing about serious institutional reforms or economic approaches or regulatory measures that might be useful to their goal of sending conspiracy theories back to their “natural habitat at the political fringe.” They barely venture into the treacherous waters of free-speech debates, including questions like whether media companies that end up pushing dangerous conspiracy theories should be held legally liable when some people endanger others using those companies’ platforms.

The authors of A Lot of People Are Saying seem most comfortable with calls for self-regulation, chiding Facebook, for example, for being “slow to recognize its civic responsibility” rather than chastising the US government for not making this behemoth company do so. And this might be because, in the end, it is hard for any of us—scholars, citizens, even the government—to ever be entirely sure about what is conspiracy-mindedness and what is just an effort to be inquisitive in the democratic spirit after all.