At the Ohio Valley Military Society’s annual Show of Shows, there is plenty for sale that isn’t Nazi memorabilia. All sorts of mementos from all sorts of wars: Civil War caps, antique pistols, Purple Hearts, samurai swords, World War I trench kits. But there is a lot of Nazi memorabilia.

At this year’s Show of Shows, which took place in February in the Kentucky Exposition Center in Louisville, there were nearly 2,000 tables, and my best guess is that at least half had Nazi items — and often only Nazi items — for sale. There were Nazi flags, busts, helmets, Lugers, cutlery, batons, an autographed photo of Hitler. A small brass swastika pin could be picked up for $20; an SS serving bowl with gold engraving, $1,000; a yellow- and white-gold Luftwaffe Pilot Observer badge adorned with 170 diamonds, $130,000.

For a while I shadowed a tall, affable dealer from Belgium who specialized in badges and who’d already spent nearly all of the $100,000 in cash he’d brought with him. He stopped at one table and efficiently inspected a couple of dozen Nazi-era Iron Crosses, whispering to me which were fake or had been modified, before settling on one he liked, or at least thought worth the $500 he paid for it.

I’d gone to the Show of Shows, the largest military memorabilia show in the country, because I wanted to better understand the trade in Nazi artifacts, to try to get a sense of these collectors, their motivations. The market for Nazi mementos is thriving — annual sales are, according to one expert, as high as $100 million — and in the United States nothing about it is illegal. (Many other countries, particularly in Europe, do have regulations, though generally they have to do with the display of Nazi symbols, not trade or possession.) It isn’t conducted in the shadows or on the dark web or only at specialty shows or only in Kentucky. Nazi items are openly sold by dealers and auction houses countrywide, at trade shows and in storefronts and online.

From Wehrmacht epaulets and belt buckles to Hitler’s top hat and Eva Braun’s underwear, if an object played a material role in the Third Reich, no matter how incidental, no matter how banal or bizarre, then it’s probably for sale. Items that allegedly belonged to or were touched by or are otherwise imbued with the spirit of a major Nazi personality, most often Hitler, can be exorbitantly expensive (even though most of these relics have an extremely questionable provenance). Last year, a watch supposedly worn by Hitler went for $1.1 million at auction.

For years I’ve seen up close the pull Nazi artifacts can exert. I’ve spent time with Polish treasure hunters seeking, and occasionally finding, any variety of objects left behind by the Nazis. But I hadn’t understood how pervasive the trade was — hadn’t understood, in fact, that it was a trade, how thoroughly these artifacts had been commodified. And I certainly hadn’t realized how the big the market was here, in the United States.

What opened my eyes was learning how much Nazi stuff there was on LiveAuctioneers, the pre-eminent online platform for antiques dealers. According to a Times Opinion analysis, the site has published more than 30,000 listings for Nazi memorabilia in the past 15 years, making it probably the biggest, and certainly the most mainstream, purveyor of Nazi artifacts in the country. Although LiveAuctioneers’ policy prohibits “items that glorify or otherwise capitalize on human tragedy with no regard or sensitivity to the suffering caused by such events,” genuine Nazi artifacts are generally exempt, as they’re considered “historical.” (Most other major platforms have enacted more stringent policies. EBay, for example, bars any item that bears a swastika, with some exceptions for currency, stamps, historically accurate models and dioramas and photos, books and art, as well as items that predate 1933.)

Only occasionally does the market make news — a journalist stumbles into a shop that hosts an auction selling Nazi-related paraphernalia or an auction attracts attention because it’s being held on Yom Kippur. And every once in a while it comes to light that someone of note has a collection of Nazi artifacts. Most recently, there was Harlan Crow, the billionaire benefactor of Justice Clarence Thomas. Mr. Crow’s collection is reported to include a couple of Hitler paintings, Nazi linens and a signed copy of “Mein Kampf.”

News that someone is into Nazi memorabilia or more generally that there’s a ready supply of and demand for Nazi memorabilia is met, predictably, with widespread outrage (if perhaps also with some measure of titillation). If no one seems all that shocked that it’s legal — the sanctity of the First Amendment is baked deep into the American psyche — then I think it’s fair to say that people are upset, or at least weirded out, that such items are bought and sold, promoted, profited from, and treasured. People cannot imagine how any non-Nazi could be into this stuff, with the corollary that anyone who is into this stuff must be a Nazi or basically a Nazi or is sufficiently Nazi-philic to warrant extreme suspicion.

The criticism and commentary are especially charged nowadays, given the increasing visibility of racist and antisemitic sentiment and rhetoric and violence, of emboldened neo-Nazis and white supremacists; downplaying the trafficking and promotion of anything Nazi as innocuous or ironic or someone’s innocent hobby feels, to many, stupid and dangerous.

This is a valid and justifiable response — it’s an excellent rule of thumb, to be on the side that’s against Nazis — but at the same time it strikes me as incomplete. It does not reckon with who the collectors are or why they collect nor does it address the principles the market is built on, or what it in fact espouses.

The truth is that many collectors of Nazi memorabilia are, in fact, collectors, a term I’m using semi-technically to describe those who dedicate themselves, often obsessively and for reasons inscrutable to the outsider, to amassing some or other class of objects, usually something interestingly varied in terms of condition, provenance and rareness — action figures, stamps, coins, Pez dispensers. This isn’t to say there’s never a profit motive, but there is, or at least at some point was, a base desire on the part of collectors to, simply, possess.

“There’s a lot to collect,” Michael Hughes, the author of “The Anarchy of Nazi Memorabilia: From Things of Tyranny to Troubled Treasure,” told me. “Absolutely, Nazi memorabilia appeals to the systematic collector who collects complete series, like baseball cards.” Dr. Hughes, an academic who describes himself as a “reformed collector” and who has interviewed or otherwise interacted with hundreds of collectors of Nazi memorabilia, says most aren’t all that strange or exceptional, at least with respect to the larger collecting community. “Generally the people I have met over the last 30 years are just your average Joes,” he said.

As one collector put it to me: “I have more in common with a Beanie Babies enthusiast than I do with a neo-Nazi.” The man with perhaps the most valuable Nazi memorabilia collection in the United States also has what is likely the most extensive collection of “Back to the Future” memorabilia, including a DeLorean used onscreen in “Back to the Future Part III.”

Of course it matters to the collectors a great deal that these objects are historical. It’s a big part of the appeal, that nerding out on World War II; it’s the lens they insist on viewing these objects through — Nazi artifacts are, they argue, just an unspecial subcategory of militaria — and in turn how they defend their practice, as a hobby, an obsession, even a form of connoisseurship that is about the furtherance of a sort of hands-on historical knowledge.

This is also effectively the stance of LiveAuctioneers as to why Nazi artifacts don’t contravene its policy regarding hateful items: that these are material remnants from a particular place and particular time, interesting and desirable strictly as artifacts, and sterile with respect to contemporary politics or ideology.

There are collectors of Nazi memorabilia who are Jewish, whose relatives died in the Holocaust. None were eager to speak with me on the record — not because they thought they were doing anything shameful but because, as one told me, “Most people don’t get it, and will never get it” — but made it clear that their fascination with Nazi artifacts in no way diluted their completely standard views regarding World War II, Nazis and the Holocaust. (When a friend of mine, who is Jewish and who’s been keenly interested in the Holocaust his entire life, heard I was at the Show of Shows, he asked me to pick him up a badge once worn by a member of the SS, the Nazi regime’s most significant paramilitary arm, explaining that he enjoyed imagining how the German officer who originally wore the thing would react to the fact that it was now being stored in a Jew’s underwear drawer.) The Nazi object’s sinisterness is not ignored but is definitely not a deterrent; if anything, it makes it more interesting. One collector I spoke to explained it in terms of “Star Wars”: Which is more compelling, he asked, the Light Side or the Dark Side?

Many collectors ascribe to Nazi artifacts the moral status of war trophies, plunder from a fallen enemy. Victorious American soldiers marched in and filled their pockets with Nazi goods, because they wanted mementos, because they were greedy, because that’s the way of war — this seems to be the preferred origin story as to how any given artifact came on the market — and any ideological ickiness thus drained away. No one would accuse those victorious American soldiers, no matter how extensive the collection, of being too into Nazis. And that decontaminated status, the collectors insist, is fixed. Even decades later, these aren’t symbols of Nazism, but souvenirs of its downfall.

This apologia is widespread. Right by the entrance of the Show of Shows, there was a large placard of two American servicemen standing atop a Nazi flag and examining Nazi weapons, with a caption saying, “These objects hold the interest of collectors today for the same reasons that our serviceman took them during and after the war: They are historic artifacts.”

Serious collectors view collecting as museological in nature, requiring expertise, research, classification, conservation. (The profiting and speculation are, in this framing, an amoral byproduct.) They will readily make a preservationist argument, claiming that if it weren’t for their obsessive accumulation, these items would be lost or destroyed. It can get downright high-minded — collectors will tell you they help ensure history won’t be forgotten, won’t be repeated. “Because ‘never again,’” one dealer said when I asked why he sells badges of the Totenkopf, a style of skull-and-bones insignia used by the SS.

I don’t know what’s happening in anyone’s heart of hearts, and I’m admittedly avoiding any lines of psychological inquiry, but from everything I’ve seen and from everyone I’ve spoken to, my sense is that, for the most part, the collectors are sincere and are not harboring any Nazi sympathies. At the same time I don’t think their sincerity or sympathies are all that germane.

The very concept of “Nazi memorabilia” is a misapprehension of these artifacts, a mistreatment of a fraught material history; it relies on and feeds an insidious distortion of World War II, which is flattened into a tale of victors and vanquished. The cruelty, the suffering, the victims, the genocide are all out of frame. History, and especially history of World War II, is never just an accumulation of facts; it’s a narrative, constructed with more or less deliberation but constructed all the same. Decontextualization can be — regardless of intentions — a form of soft revisionism.

At the Show of Shows, I experienced an initial shock at seeing all that Nazi merchandise, and an ancillary shock at seeing all those ready customers, but once that wore off — which didn’t take long, it was what was normal there — something else disconcerting came into focus. In this huge hall so proudly dedicated to history, full of men so passionate about the past, so committed to its preservation, who pride themselves on their arcane knowledge of World War II, some of whom will unhesitatingly invoke “never again” as a justification to trade SS badges, the Holocaust was almost entirely absent. Or really any indication at all that the Nazis were guilty of anything beyond being defeated.

I realize a trade show doesn’t purport to be a classroom, but even so, the Holocaust’s absence is demonstrative of where the emphasis is being placed. I don’t mean to accuse the organizers of any sort of malice — in fact it’s a semi-enforced etiquette to not display anything considered “hateful,” like overtly antisemitic Nazi propaganda posters, and certainly no Holocaust items, which are widely considered within the community to be beyond the pale. (On my last day at the show I came across a yellow star, but was quickly informed that it was in fact unworn — it had come from an uncut roll seized by Allied soldiers straight from the factory and so was still technically a war trophy.) This is a well-intentioned boundary, but it puts into relief the void at the center of this approach to this history.

As a historical stance it’s toxic, and it seeps. Rampant in the collecting community, if to varying degrees, is something called the myth of the clean Wehrmacht, which posits that the Wehrmacht, Nazi Germany’s conventional armed forces, was just a regular military, no more or less ethical than other militaries, just doing regular military stuff, and it was the SS that did all the nasty work.

This is a reprehensible take, not only because it’s so spectacularly and famously inaccurate — the theory had a strong hold in Germany until the 1980s when the country began to come to grips with its own history — but also because at its core it’s a repudiation of moral responsibility. It’s whatever the opposite of “reckoning” is.

The theory’s appeal to the collectors is obvious: It’s a moral scrub, removing what’s unappealing and difficult to market, so what remains is clean and collectible. There’s a similar sort of negationist warp in many of the books and catalogs that trace and categorize the artifacts; these catalogs are written or informed largely by former Nazis, who are subtly or not-so-subtly laundering their wartime histories. Even the lot descriptions give away what, in this world, World War II is and is not about. Dr. Hughes, in his book, notes a dealer’s description of Hitler’s chair and desk set: “This simple piece of furniture is one of the most iconic and important items in World War II history.”

Turning Nazi artifacts into tradeables, far from fulfilling some sort of preservationist mandate, in fact mutes what’s historically meaningful about them. The purpose of preservation is not merely to ensure artifacts aren’t lost or damaged, but to place them in proper context, to narrativize them.

Without that context, Nazi artifacts only represent a fascination with and commodification of Nazism; what’s being traded and promoted is Nazi symbology. The claim that a Nazi artifact is so rigidly “historical” as to be apolitical is at best oblivious, if not dismissive, of how these symbols are deployed today, to what they mean to most people, to their very current political implications. The world in which a swastika was a dead and sterile symbol, in which it wasn’t the go-to badge of increasingly visible and unashamed neo-Nazis and white supremacists — this would be a much improved world.

The collectors and especially the platforms rely on and hide behind the “historical” as a moral criterion, that it’s OK as long it’s authentic. But it doesn’t work like that: You can’t contain a symbol’s meaning and power and reach. Individuals, maybe, can hold steady the line between fascination and fetishization, between obsession and glorification, but collectively it’s impossible.

The depoliticization of the swastika, even or especially in the name of “history,” has potent effects that go beyond the world of collectors. It sanitizes the symbol, makes it that much less charged, that much more mainstream, and in turn helps legitimate those who rally around it. There’s no non-hateful version of a Nazi symbol, in other words. The insistence that just because it’s historical it’s innocent is misguided. Sure, this particular artifact may be a piece of history, but what it espouses is very much not behind us.

The more time I spent in the world of Nazi memorabilia collection, the more I spoke with collectors and scholars and the platforms, the more clear it became to me that, ideally, the artifacts should be in public custodianship. Contrary to many collectors’ protestations, essentially no one is calling for the destruction of history. Public and public-facing institutions such as museums and archives can preserve and make accessible even the ghastliest material history, and can do so responsibly, treating artifacts not as collectibles or relics but as elements of a story. Public custodianship also functions as a kind of spiritual safekeeping, upholding the historical value while suppressing monetary or sentimental or even mystical value. The United States government has in protected storage an enormous collection of Nazi art and artifacts, including a few paintings by Hitler. It doesn’t know what to do with any of these items, so it simply holds on to them, which is exactly right.

Tellingly, with respect to the material history of World War II, the (responsible) museum is basically the inverse of the collector. The United States Holocaust Memorial Museum does not accept weaponry — the bread and butter of the Nazi memorabilia market — because Nazi weaponry does not illuminate the story the museum is dedicated to telling. But the Holocaust-related items — which to the (responsible) collector are beyond the pale, which are considered un-collectible (and are often unsellable) — are what the museum is built on, because these items bear witness to the consequences of Nazi ideology.

I recognize that this is an ideal, not a solution. There’s no enforcement mechanism to ensure that these artifacts end up in the hands of museums and historical organizations; the First Amendment seems to forestall regulation of the sale or possession of Nazi artifacts. (That said, there are some instances in which a moral code regarding the possession and trade of an object is legally enforced — certain antiquities and Native American cultural artifacts, for instance, and, interestingly, Medals of Honor, which by law cannot be bought or sold.)

But I don’t believe that means there’s nothing to be done; it only means our response isn’t legislative. If the goal is to counter the normalizing and sanitizing of Nazi symbols, then the market corrective, as it were, is to stigmatize — to articulate and defend moral boundaries, to assert and reassert what’s tolerated and what’s beyond the pale.

Outrage can be effective, but it has to be harnessed and it has to be directed. Otherwise the debate never gets past whether or not some guy is a crypto-Nazi or whether some item is sufficiently “historical,” and that gives cover to the market participants, allowing them to frame it as an issue of censorship or First Amendment rights. It all just crumbles along the usual battle lines.

However upset you personally are by Nazi memorabilia, the fact is that the corporations that traffic in them, most prominently LiveAuctioneers, do not face sustained blowback, because otherwise they’d stop. Their policies reflect what they believe they can get away with, both in the court of law and of public opinion.

LiveAuctioneers considered but ultimately turned down my request for an interview; instead it directed me to a “statement on vintage items with hateful imagery,” by the company’s former chief executive, Phil Michaelson. (The page has since been taken down.) Mr. Michaelson opens with an anecdote about how his rabbi used an SS hat to inspire his Yom Kippur sermon, then warns that “censorship is a very slippery slope” and laments that it is “hard to determine what may or may not be considered” as “an object worth retaining for posterity.” He worries that “eliminating history” can “make us more likely to repeat past atrocities.”

An instructive counterexample is eBay, which over the last two decades has learned (or been forced to learn, depending how you want to see it) what the public is willing to stand for, what the company stands for.

“When I started with eBay it was a different world,” Wolfgang Weber, the company’s associate general counsel, told me. “In the U.S., there was no concern at all that democracy could be at risk. Instead, there was a view that freedom of speech is a constitutional right.”

But eBay’s policy evolved. Eventually the company, after several controversies, and after consulting with historians and Holocaust survivors, “landed on the decision to ban these items,” Mr. Weber said. “It’s important that these items are preserved but we found in the end that eBay is not the right place for this. These items belong in a museum.”

At the Show of Shows I watched a teenage boy, maybe 15 or 16 years old, browse a table of Nazi daggers. There was one he really liked, but it was expensive; he told the seller he wasn’t sure he could afford it. The seller nodded and pulled out a similar-looking dagger, which was half the price.

The boy was suspicious. “What’s wrong with it?” he asked. “Nothing,” the seller said. “There’s nothing wrong with any of them.”

Methodology

To report this story, Times Opinion compiled a data set of LiveAuctioneers listings for Nazi memorabilia. The data set includes unique listings that appeared in the search results for the following terms: “Adolf Hitler,” “Nazi swastika,” “Nazi Heer,” “Nazi Kriegsmarine,” “Nazi Luftwaffe,” “Nazi SS,” “Schutzstaffel,” “Third Reich” and “Wehrmacht.” Listings categorized as books or that included the word “book,” “hardcover” or “paperback” in their title were removed from the data set. All listings were from auction houses located in the United States.

The auction items shown throughout the story were pulled from actual LiveAuctioneers listings, which have been edited for clarity. Times Opinion has not authenticated the listings.

Menachem Kaiser (@menachemkaiser) is the author of “Plunder: A Memoir of Family Property and Nazi Treasure.”

Data analysis, design and development by Gus Wezerek.

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