What is sophistry? It’s a kind of slick pseudo-logic, a set of arguments that are superficially persuasive but deeply and dishonestly flawed. The hallmark of sophistry is the contrast between how much sense it seems to make and how little sense it actually does make when you stop to think about it. Someone making a sophistical argument seems incredibly logical and rational. Even as the arguments they make are revealed under scrutiny to be patently absurd, an uncritical listener might easily be tempted to believe them.

Dinesh D’Souza is a sophist, and a good one. Most people on the left probably won’t appreciate just how good he is. Seeing the title of his new book, The Big Lie: Exposing the Nazi Roots of the American Left, they’ll snort derisively. A book like this, they’ll say, is so self-evidently absurd that there is no need to even bother with it. Even to call it sophistry is to pay it too great a compliment. Sophistry is subtle and persuasive. Calling the left Nazis is not persuasive, and it certainly isn’t subtle.

One of the many harmful tendencies on the political left, however, is the failure to understand how things appear to people who are not already leftists. This is what prevented so many people from appreciating the threat posed by Donald Trump: actions that looked like PR catastrophes or disqualifying embarrassments to a progressive simply did not look the same to non-progressives. They’ll treat The Big Lie the same: too silly, don’t even engage with it. Thus, even though according to Publisher’s Weekly, D’Souza’s book is currently the #1 bestselling political book in the country, the only major media outlet that has reviewed it has been the U.S. News and World Report, which wrote it off as “dull” and “dumb.”

A major reason not to take The Big Lie seriously is D’Souza himself. By mainstream standards, D’Souza’s career has been a comical embarrassment. D’Souza first found notoriety while an undergraduate at Dartmouth, where the student publication he edited outed members of the Gay Student Alliance. He became a prominent conservative pundit with his book Illiberal Education, but by the 2000s he had, in the words of Vanity Fair, “eaten away at his respectability in intellectual circles” with extreme and often bizarre claims. He blamed 9/11 on Hollywood liberals, saying that Osama bin Laden was primarily motivated by a hatred of Western sexual decadence, an argument that put off conservatives with its implication that bin Laden shared their values. His The Roots of Obama’s Rage argued that Barack Obama was a conduit for his father’s radical anti-colonial politics, with the “philandering, inebriated, African socialist [Obama, Sr.] now setting the nation’s agenda through the reincarnation of his dreams in his son.” Even the conservative Weekly Standard called this “lunacy.” Further embarrassments followed. In 2012, he was forced to resign as president of a Christian college after allegations of adultery. In 2013, D’Souza recorded an infomercial for pop-up Christmas trees. And in 2014, he pled guilty to a felony campaign finance violation, spending 8 months at a halfway house. (D’Souza alleged political persecution by the Obama administration, tweeting: “MLK was targeted by J. Edgar Hoover, an unsavory character; I was targeted by the equally unsavory B. Hussein Obama.”

Importantly, though, while D’Souza was discrediting himself more and more among the elite intellectuals who had once treated him as a serious thinker, he was building an audience elsewhere. D’Souza was embraced by Evangelical pastors like Rick Warren and made a fortune on the megachurch circuit. His books became bestsellers. His polemical documentaries, like Obama’s America and America: Imagine a World Without Her, attracted huge audiences despite being critically panned. As with Trump, the fact that mainstream institutions declared him an “embarrassing failure” by their standards didn’t mean that he was one by everybody else’s. It’s easy to call him “fringe.” But a lot of people live on the fringes, and they buy Dinesh D’Souza’s books.

The argument of The Big Lie is that you have been lied to all your life. Since you were a schoolchild, you have been told that Nazism and fascism were “right-wing” ideologies. You have been told that left-wingers hate fascism, that they reject racism, totalitarianism, militarism, and all of fascism’s other constituent ideological parts. But this has been a calculated falsehood. In fact, the progressive left have always been the real Nazis. And they have covered it up by using Adolf Hitler’s infamous concept of the Big Lie, the lie so “colossal” that nobody would believe anybody “could have the impudence to distort the truth so infamously.” The progressive left calls the other side Nazis to disguise the fact that they, themselves, are Nazis. Every time a progressive accuses another party of fascistic behavior, it will be the progressives themselves who have acted like fascists. They call President Trump a fascist to disguise their own fascism. But fascism has always been fundamentally left-wing, and American conservatives must get serious about eliminating the threats posed by the Nazis in our midst, i.e. the left.

So far, so barmy. The book’s thesis can be boiled down to the statement: “No, You’re The Nazis” (which, frankly, I think ought to have been the title). It’s obvious why hardly anybody on the left thinks this worth bothering with. Its thesis is politically childish and historically ignorant. It is a fundamentally stupid book. Once again, though, note the parallel: Trump, too, is childish, ignorant, and stupid. But he was also, to some people, persuasive, and he is now the President of the United States.

People who choose not to read The Big Lie will miss something: it’s actually somewhat persuasive. It’s wrong and deranged, but the ongoing conflation of “being right” and “being persuasive” is one of the reasons people believed nobody as wrong as Donald Trump could be so successful at winning support. The Big Lie is sophistry, and like all good sophistry, the ordinary person who reads it will come away, if not convinced, at least slightly unsettled and unsure of themselves. And while it’s possible to refute most of the book in under a paragraph (stay tuned), it would be unwise to assume that just because D’Souza is delusional, this is a badly-written book. It is a well-written book, persuasive and carefully-sourced. It may be difficult for some people to accept that any book with The Big Lie’s thesis could have these qualities. But it does, and understanding that it does is important for leftists, who shouldn’t laugh off people like D’Souza.

Let me go through and give you a potted version of The Big Lie. You will probably find it ridiculous for any one of ten zillion reasons. But instead of mentally arguing with the propositions, and identifying fallacious reasoning, I’d like you to focus on something else: namely, how the argument as a whole might be persuasive to someone, and why it works rhetorically.

Nazism, D’Souza says, is leftist, and leftists have been trying to cover this up. But, in an important rhetorical move, D’Souza acknowledges that the reader probably finds this proposition difficult to believe. He says, however, that this is because the reader has been brainwashed. And he asks the reader to set aside their preconceptions about the argument, to allow D’Souza to present the evidence and then to judge the case on this basis. We start with the history of Italian fascism and German Nazism. Benito Mussolini began as a socialist, heading the Italian Socialist Party. Even when Mussolini replaced his old class analysis with a belief in the primacy of the Italian nation, he was a communitarian who believed that fascism was a “true socialism” that countered “plutocratic elements.” Likewise, while leftists have always tried minimize the “Socialist” aspect of “National Socialism,” Hitler himself said: “We are socialists. We are the enemies of today’s capitalist system of exploitation… and we are determined to destroy this system under all conditions.” Hitler condemned the United States as “a country where everything is built on the dollar.” At its root, both fascism and progressivism are concerned with the same goal: empowerment of the state and the subjugation of the individual.

It may seem crazy to compare Hitler and Mussolini with American progressives, D’Souza acknowledges. But the affinities have always been more significant than the left would like to admit. Nazi philosopher Martin Heidegger has been a favorite of radical leftists. And when we look at some of the “progressive heroes” among U.S. presidents, we see racist and totalitarian tendencies. Let us take, for example, Wilson, FDR, and Kennedy. Woodrow Wilson was an unabashed white supremacist who segregated the civil service and screened Birth of a Nation at the White House, touching off the rebirth of the KKK. He also launched an unprecedented crackdown on civil liberties, jailing critics of his war policies. When John F. Kennedy came back from a visit to Nazi Germany, he wrote in his diary that “I have come to the conclusion that fascism is right for Germany and Italy,” and that “the Nordic races appear to be definitely superior to their Latin counterparts.”

As for Roosevelt, he almost became an outright dictator. Mussolini himself said that he “greatly admired” Roosevelt, whose singular control of the government was “reminiscent of fascism.Roosevelt hosted Mussolini’s aviation minister, Italo Balbo, at the White House and presented him with the Distinguished Flying Cross (the New York Times said Balbo left the White House “with his face wreathed in smiles,” and Balbo wired Mussolini to say “the existence of anti-fascist sentiment abroad is a myth… exploded by the enthusiastic welcome my air squadron has received in America.”) Roosevelt called Mussolini that “admirable Italian gentleman” and wrote that “I am much interested and deeply impressed by what he has accomplished.”

Roosevelt was odious in other ways. He maintained segregation in the armed forces and New Deal agencies, placed more than 120,000 Japanaese Americans in what he himself called “concentration camps,” and cooperated with racist Southern Democrats in their efforts to block anti-lynching legislation. Roosevelt appointed a former Klansman, Hugo Black, to the Supreme Court, and Black recalled that Roosevelt had been fine with his KKK membership: “President Roosevelt told me there was no reason for my worrying about my having been a member of the Ku Klux Klan. He said some of his best friends and supporters he had in the state of Georgia were among members of the organization. He never indicated any doubt about my having been in the Klan nor did he indicate any criticism of me for having been a member of that organization.” When the Supreme Court overturned the National Recovery Act as unconstitutional, Roosevelt threatened to pack the courts with compliant idealogues. His aide Harry Hopkins said “we have lawyers who will declare anything you want to do legal.” What could be more totalitarian?

Liberal American intellectuals were also sympathetic to fascism. The New Republic’s editor had warm words for Mussolini, for “arousing in a whole nation an increased moral energy.” Gertrude Stein said Hitler should get the Nobel Peace Prize. Left historian Charles Beard called fascism “ an amazing experiment in reconciling individualism and socialism.” Columbia University economist William Pepperell celebrated the New Deal as a kind of “Fabian Fascism.” Columbia itself “maintained friendly relations with Nazi academic institutions and representatives of Nazi Germany.” When a Harvard alumnus, Ernst Hasnfstaengl, became the head of the Nazi press bureau, The Harvard Crimson called for him to receive an honorary degree “appropriate to his high position” in a “great and profound nation.” A number of Harvard faculty attended a gala at the docking of a Nazi warship in Boston, and a Harvard delegation attended a 1936 celebration at Heidelberg University, which the British had boycotted for being a Nazi propaganda event.

But, D’Souza contends, nobody should be surprised by this. For the history of progressivism and the Democratic Party is a history of vicious racism, dating back to the beginnings of the Democrats under Andrew Jackson. Jackson was a brutal slaveowner, proud of his reputation as an “Indian killer.” He massacred Creek refugees, writing to his wife that “it was dark before we finished killing them.” Jackson “used a combination of trickery, threats, and murder to evict native Indians from Florida, Alabama, Mississippi, and Tennessee,” was responsible for the Indian Removal Act and the Trail of Tears, and declared that “the whole Cherokee nation ought to be scourged.” Jackson’s administration was brutal in its treatment of Indians, and treated them as less than human, with Secretary of State Lewis Cass declaring that “the Indian is a child of impulse” who is “unrestrained by moral considerations.”

From the Jacksonian Democrats to Wilson’s progressives, the Democratic Party remained racist to its core. The KKK was for many years, according to left historian Eric Foner, “the domestic terrorism arm of the Democratic Party.” Republicans were the party of abolition and Reconstruction, while Democrats were the party of slaveowners and segregationists. In the early 20th century, the “progressive” movement added another type of racism to the mix: eugenics. Turn-of-the-century progressives were enthusiastic supporters of eugenics, with birth control advocate (and Planned Parenthood forerunner) Margaret Sanger even giving a speech on eugenics to a meeting of the KKK, and in 1933 Sanger’s Birth Control Review magazine published an article by Nazi eugenicist Ernst Rudin.

In fact, the Nazis were directly inspired by the actions of the Jacksonian Democrats and the progressive eugenicists. Hitler “praised to his inner circle the efficiency of America’s extermination—by starvation and uneven combat—of the red savages who could not be tamed by captivity.” Hitler was impressed by the writings of American eugenicists, and called environmentalist Madison Grant’s The Passing of the Great Race his “Bible.” He reported to have “studied with great interest the laws of several American states concerning prevention of reproduction by people whose progeny would in all probability be of no value or injurious to the racial stock.” American progressive eugenicists, and American race laws from the Democratic South, directly inspired the Nazi Nuremberg laws.

Thus, D’Souza concludes: the idea that Nazism was “right-wing” and progressivism is “left-wing” is a fabrication, designed to obscure the fact that fascism, Nazism, communism, and Democratic ideology are united by a common commitment: to the totalitarian state, and to disguising racism beneath the rhetoric of social improvement. And today, when progressives criticize Donald Trump as a “fascist,” the same thing is going on. In fact, they are the fascists: they are the ones who believe in silencing other people, by shutting down conservative speakers. They are the ones who believe in racism, through affirmative action and the continuation of eugenics through abortion. Conservatives are for individual liberty, Democratic progressives are for the totalitarian state, and thus just like Wilson and FDR, it is they who are the fascists.

Alright, so we can see how everything goes off the rails when D’Souza tries to talk about the present. In these parts, the arguments really are of the “Hitler was a vegetarian” type. At one point, D’Souza even says that because Nazis were interested in race, and Democrats are interested in race, Democrats are Nazis. D’Souza also tries to conclude, from the argument presented, that we should reduce taxes on the wealthy and repeal Obamacare, because it’s the only way to fight fascism. The explanation, to the extent it can be discerned, is that because Mussolini controlled the economy, and because FDR liked Mussolini and also wanted to “control the economy,” all government intervention in the economy makes you Mussolini. This reasoning… does not hold up.

The rest of this is easy enough to decimate, too. D’Souza’s tactic is to show that in the past, a number of people who have used the word “Democrat” to describe themselves have done horrific things. First, of course, today’s Democratic Party might share the name of Andrew Jackson’s Democratic Party, but that does not make today’s Democrats Jacksonians. But, more importantly,if you define yourself not as primarily as a “Democrat” but as an “opponent of horrific things,” D’Souza has proved nothing whatsoever about your politics. If your loyalty is not to a label but to some consistent set of principles, you have nothing to fear from D’Souza exposing the history of the Democratic Party as a history of slavery, eugenics, and terrorism. Yes, it’s true, if you’re invested in proving that Woodrow Wilson and FDR were admirable, a lot of the facts in the book may make you uncomfortable. If you want to salvage the reputation of Harvard and the New Republic, you’re going to have a tough time. But if your starting point is “Racism, slavery, murder, and totalitarianism are bad things,” then this book’s criticisms do not affect your kind of leftism in the slightest.

The funny thing about all of this is that half of it could have been written by Howard Zinn or Noam Chomsky. The Big Lie is unusual for a conservative book, in that it doesn’t try to whitewash the history of slavery or the genocide of Native Americans. D’Souza calls it genocide, and he goes into detail comparing life on slave plantations to life in German concentration camps. He shows how the history of America contains a long track record of lynchings, forced sterilizations, and massacres. He admits that the Nazis took direct inspiration from U.S. laws, and says that even the Nazis found the American “one-drop rule” for determining “black blood” to be too strict. But for D’Souza, none of this indicts “The United States.” It indicts “Democrats” and “progressives.”

It’s kind of a novel argument, honestly. I’ve certainly never heard it before. Usually conservatives seem to want to justify the internment of the Japanese, or to emphasize that most Indians died from diseases rather than direct killing. They wouldn’t be terribly comfortable with the idea that American laws inspired the Nazis, because they like to think of America as, on the whole, pretty racially fair with the regrettable exception of slavery. Not D’Souza. He admits all of it, but says it was the liberals who did it.

As I say, logically speaking, this is not an effective maneuver, because it only works against someone who is trying to salvage the reputation of early 20th century Democrats. If you’re a libertarian socialist like Zinn or Chomsky, and you are a committed opponent of every kind of tyranny, whether it calls itself progressive or not, D’Souza has just proved your entire case for you. If you are like George Orwell, a socialist whose socialism is defined in part by its skepticism of state power, it means nothing for anyone to prove that Hitler said he was against capitalism. (Although Hitler also clarified in 1930: “Our adopted term ‘Socialist’ has nothing to do with Marxian Socialism. Marxism is anti-property; true socialism is not” and said that socialism in the leftist sense was “a Jewish conspiracy.”) If you are like the endless numbers of socialists who have despised racism and totalitarianism, and haven’t flirted with state-worship, every argument in this book can instantly be proved worthless.

Why, then, do I think the book is effective? Because the argument is still a well-crafted piece of sophistry, backed with some solid, though dishonestly selected, historical sources. (I say “solid” because he relies on mainstream liberal historians like Eric Foner, Ira Katznelson, and Timothy Snyder, and “dishonestly” because D’Souza selects everything that could support the idea of a “liberal” sympathy for fascism and ignored every piece of evidence of a right-wing sympathy for fascism; he plays up the “socialist” element in National Socialist even though this was trivial, while ignoring the “national” aspect, which was the center of the doctrine. He has to, because leftists have historically been defined by their skepticism of nationalism: “Workers of the world, unite!”) And a lot of people do identify themselves more by labels than principles, downplaying the crimes committed by their “side” and highlighting those committed by the other side.

So, yes, the book is full of silly arguments, using endless “guilty by association” type fallacies, selecting its evidence prejudicially, and relying on the ludicrous idea that if ever a “Democrat” did something, then Barack Obama can essentially be held responsible for it. But the book is deeper than it looks: D’Souza has done some research, and has long discussions of the proto-fascist syndicalism of Georges Sorel and Lenin’s ideas about imperialism. It’s sophistry, but sophistry works. Certainly, D’Souza’s book is better than large amounts of nonfiction that comes from our side, which is not nearly this accessible or clear. He actually responds to anticipated counterarguments, and has clearly read a lot of left writing, which is more than can be said for leftists who comment on the right. I don’t wish we wrote books this dishonest, but I do wish we wrote books this readable.

It’s time to start taking this stuff seriously. Historians have got to respond to books like D’Souza’s, and they have to do so in depth. They need to concede the points that are right, and vigorously contest the points that are wrong. It may seem like this is “beneath criticism,” but nothing is beneath criticism if large numbers of people believe it. And while Dinesh D’Souza may appear a laughingstock from the vantage point of the academy and the press, his books continue to quietly sell hundreds of thousands of copies.

And that’s scary. Because this book isn’t innocuous. D’Souza’s ultimate conclusions are downright frightening. Just as certain parts of the left believe that if someone is a “fascist,” they no longer have rights and you can do as you please to them, D’Souza calls for all-out war on the left, which he says is necessary to stop “Nazism”: “This will require, from the Right, a new creativity, a new resolve, and a new willingness to use lawful physical force. Anyone who says physical force is out of bounds does not know what it means to stop fascism.” People should be “duct taping Antifa thugs to lampposts,” D’Souza says, and “we should not hesitate to unleash the law and the police on these leftist brownshirts.” He even advocates using every arm of the government as a means of political repression, saying that Trump should “deploy the IRS, the NSA, and the FBI against the Left” and should stuff the Supreme Court with as many openly ideological justices as possible. All of this is justified, he says, because it is exactly what the “left” does, and anything is justified in beating them. It’s a chilling conclusion. But it’s all the more reason not to ignore the people who purchase books like this. Like fungi, ideas like these can grow in the dark, and by the time you notice them, it may be too late to stop them. I don’t know who the “real” Nazis are, but I certainly know I don’t want to be on the receiving end of whatever is directed against those who end up tagged with the label.