Everything can be defended in some way or other. The defenses aren’t necessarily good. But you can always come up with a series of words, something sounding like an argument, to “justify” nearly anything you’d care to do, no matter how heinous. Because there’s always an argument available, one that may sound strong even if it’s actually atrociously weak, it can be extremely difficult for the truth to compete. In theory, when the person who is right and the person who is wrong enter into a discussion, the person who is right will triumph in the “marketplace of ideas.” In reality, the marketplace of ideas is very similar to an actual marketplace, where flimsy products can look superficially similar to quality ones, and people have trouble knowing whether they’ve bought a “lemon” until they get it home.

When I say there are justifications for everything, I truly mean everything. You can make an argument against democracy or against empathy. (“People don’t know what’s in their best interests,” and “Excess compassion impedes rational decision-making,” respectively.) If I want to seize the land of native peoples, destroy their property and force them into exile, I might say: Land should be put to its most efficient and productive use, and while we respect the ancestral rights of all people to their homes, all benefit alike from the development of resources toward their optimal functions. In fact, even today there are those who defend colonialism, saying something like “colonialism improved living standards in the aggregate and was therefore more beneficial than detrimental.” Even slaveowners had arguments: In addition to their crackpot racial theories, they said that dominance of man over man was the natural way of things, and that slaveowners treated their slaves better than industrialists treated factory workers. (If your defense of your actions is “I’m not as bad as the capitalists,” your actions are probably indefensible.)

I could come up with a utilitarian justification for blowing up the universe and exterminating all of humanity (it alleviates suffering), an argument for cheating on your taxes, or an argument for racial profiling (stereotypes are rational). There have been arguments for invading Iraq, arguments for bombing Hiroshima, arguments for massacring unarmed Palestinian protesters, arguments for eliminating free speech, arguments for scrapping fundamental constitutional rights, arguments for purges and guillotines and show trials. Ayn Rand made the case for The Virtue of Selfishness. Hitler and Stalin each made arguments. Terrorism, assassination, torture: Each have their defenders. Osama bin Laden made an argument for 9/11, the United States justified atrocities in Vietnam as serving the national interest.

Look at what public relations people do. Their job is to come up with justifications for whatever their clients engage in, and they always can. When it was revealed that Burberry burns all of its unsold handbags in order to keep the prices high, the company had a justification. When Spirit Airlines extorts and mistreats its customers, it justifies its actions. Rarely does any company say: We did this because we sociopathically pursue our own gain at the expense of others. Instead, they appeal to values that people share: mutually beneficial transactions, sustainability, necessity, etc.

In fact, there’s a libertarian philosopher who wrote an entire book called Defending the Indefensible about how various despised members of society (e.g., slumlords, price gougers, pimps, employers of child labor, corrupt officials, litterers, scabs) are Actually Good. I haven’t read the book, but I’m pretty sure I can guess how it goes: Slumlords provide housing that otherwise would not be available, price gougers provide necessary supplies at fair market prices, corrupt officials make government more responsive, employers of child labor make families less poor, pimps facilitate transactions, scabs provide needed labor, etc. The only one I have trouble guessing is “litterers,” but I’d imagine it has something to do with efficiency or personal freedom. I am certainly not surprised that one can come up with a case for littering since, as I say, you can make an argument for anything.

Sometimes the arguments for horrible things even sound quite persuasive! Consider how the kind of “ends justify the means” logic used by revolutionaries can proceed:

The people are oppressed and cannot be saved by bourgeois government, they need a revolution. A revolution needs leadership. If the leadership is undermined, the revolution will fail. The leadership is therefore justified in searching out and eliminating counterrevolutionaries. Anything that has the effect of impeding the revolution is counterrevolutionary. Questioning the leadership of the revolution impedes the revolution.

You can see how, through a few argumentative steps, it’s easy to produce a justification for a small number of authoritarians crushing all dissent in the name of the popular will.

Most people who do evil things do not actually think of themselves as evil. They think of themselves as the good guys. Even murderers often think they are doing the right thing: carrying out an act of justice, giving someone what’s “coming to them.” CIA torturers think they are protecting their country, soldiers either think they are murdering for a good cause or that they are just faithfully carrying out a job that someone has to do. Jeff Bezos probably thinks of himself as a good person, somehow. (I’m a job creator. I deliver packages to millions of happy people. I am making the world more efficient.)

This fact is rather chilling, because it means we always need to be on guard against the possibility that we are the ones rationalizing bad things. When anything can be justified, it’s very easy to convince yourself that what you’re doing is okay. One thing I try to do is check whether I’m telling myself a “reassuring story” or actually examining the facts in the world and being self-critical. When you don’t do this, you just end up coming up with whatever arguments support the position you already held. Milton Friedman, for example, famously had an argument for why free markets were the best way to fix racial discrimination. In reality, free markets hadn’t fixed racial discrimination: Even outside the South, where discrimination was not enforced by law, business owners routinely discriminated against people of color without going out of business. And the exploitative sharecropping system was a free market system: It was a form of racist feudalism that persisted in part because white people had disproportionate wealth and therefore disproportionate power. If you are a free market ideologue, however, you will just come up with whatever arguments allow you to maintain your libertarian convictions in the face of the evidence. As I have shown, this is exactly what the Cato Institute does: It has lots of arguments, but they are arguments of convenience, made using whatever evidence will allow them to prove that libertarianism is correct.

There are plenty of “factories” out there churning out arguments that you can pluck and use to defend yourself. Every day, the Wall Street Journal op-ed page has about nine different arguments for conservative positions that readers can internalize and deploy against others. The arguments are often absurdly sloppy, offering totally unjustified broad conclusions and ignoring contrary evidence, but it doesn’t matter. Op-eds aren’t meant to be thoughtful inquiries into both sides of an issue. They’re a short string of talking points, intended to put arguments into the discourse. And they’re very effective—research does show that people change their minds after reading op-eds.

This is partly because most people do not investigate arguments very closely. They are not lawyers or philosophers. They do not have time or patience to pedantically examine every point to see if it holds up under exacting scrutiny. They look much more at packaging: Does this sound persuasive? And if there’s no time to carefully expose why an argument is bad, a fascistic argument can end up sounding no less well-made than a humanistic one. I see why my fellow leftists have a skepticism of in-person debate: You get two people side by side on a stage, both will have arguments, both will be extremely confident, and many people won’t know how to decide between them. If one side is advocating something monstrous, that’s not good. It’s made worse on cable news: Here’s two minutes from a person who thinks immigrants are human beings, here’s two minutes from someone who doesn’t. I understand why people are reluctant to engage in these kinds of debates: They’re stacked against you and very difficult to do any good with.

I once wrote in favor of free speech, saying that because “Holocaust deniers have no arguments” it is best to let them speak. I think I was wrong, not about the free speech part, but about the arguments: They have lots of arguments. They don’t have any good arguments, because ultimately they’re trying to prove a demonstrably false proposition. But they will definitely throw arguments at you! I do believe that if a fringe viewpoint becomes mainstream, you need to engage with it in order to persuade people not to hold it. However, that involves making sure that the format of the discussion actually allows you to expose the position for what it is. That’s one reason I prefer written debates: In writing, it’s much harder to use rhetorical tricks to paper over the flimsiness of your arguments. I can ruthlessly dismantle your position over 17,000 words.

There are better and worse arguments, but if you have a superficial public discourse, it may not always be obvious which is which. And that’s terrifying, because if arguments aren’t pushed, if lazy punditry is allowed to substitute for substantive reasoning, then arguments for patently immoral and false things will be treated as credible. One reason atrocities happen so often is that they’re so easy to justify, and those justifications are often never challenged. Interviewees get away with absolutely outrageous claims. (A rare exception: John Dickerson of Face The Nation pressing Mitch McConnell on his bad history.)

A good thing to remember when you hear slick, voluble, opinionated people spouting off is: It’s incredibly easy to come up with opinions and defenses for those opinions. Actually proving that those opinions are justified is very, very different, but people can have entire careers as public commentators while saying things that are obviously false. It would be nice if you couldn’t actually make arguments in favor of untenable positions. Unfortunately, you can, which means we need to know how to shut this stuff down. Personally, I think that is best done through highly effective, well-disciplined counter-speech rather than the stifling of free expression. But so long as there are atrocities, there will also be intellectual rationalizations of those atrocities, and we must never assume that just because something is indefensible it is impossible for someone to defend it.