100 Objects #2: 60-Degree Screw

Summary

99% Invisible – 100 Objects #2: 60-Degree Screw (May 29, 2026)

Episode Overview

This episode, hosted by Roman Mars with historian Daniel Ammervar, delves into the story of how one seemingly mundane object—the standardized 60-degree screw thread—became a linchpin in the construction of the modern world. It explores the chaos before standardization, the bureaucratic wizardry of Herbert Hoover, and how America’s “invisible empire” of standards continues to shape global industry, politics, and even culture. The episode highlights forgotten battles over minutiae that underpin our daily lives, ultimately demonstrating that sometimes the most profound transformations are hidden in plain sight.

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Key Discussion Points & Insights

The Anarchy Before Standards (01:28–04:46)

• Baltimore Fire of 1904: The lack of standardized fire hydrant connections meant out-of-town firefighters couldn’t help, resulting in the destruction of over 80 city blocks.
• Widespread Incompatibility: There was general chaos around measurements (e.g., a bushel of greens different in each state), truck sizes, even the dimensions of a football and the meaning of traffic lights.
• Quote:
  “The early 20th century was the wild west for standards. Everywhere you went, things were just defined differently.” – Roman Mars (03:20)

The Humble Screw as Megastandard (04:20–05:42; 10:42–14:13)

• Screw Threads as Civilization’s Skeleton: The screw, or more specifically, the angle of its thread, is what holds much of the mechanical world together.
• Screw Thread Variation: Even a tiny, almost invisible difference in thread angle (e.g., 55 vs 60 degrees) made equipment incompatible.
• Mega-Standardization: Creating one standard for screws was more significant than for any other product, impacting every industry.
• Quote:
  “The screw thread is a simple device, but it ties together the whole mechanical skeleton of our civilization.” – Daniel Ammervar (04:46)

Herbert Hoover and the Drive to Standardize (06:08–09:17)

• Hoover’s Obsession: Hoover, later known for the Depression, was “ideologically obsessed with standardization” as Secretary of Commerce. He believed making things more efficient would end conflict between workers and bosses.
• Diplomatic Bureaucracy: Rather than making laws, Hoover convened endless meetings with manufacturers, persuading them to agree on dimensional standards for everything imaginable – not just bricks or cement, but also the number of hours a glass tumbler should withstand boiling water.
• Quote:
  “His move is just to get the manufacturers to agree. And apparently, he’s shockingly persuasive in doing so... what a weird technocratic strategy. But he’s like, all of these arguments are just about slight profit margins, and we can get far larger ones if we can get everything to be more efficient.” – Daniel Ammervar (06:58)

The Moment of the 60-Degree Thread (12:54–14:13)

• The 1924 Agreement: Under Hoover, US manufacturers agreed to the 60-degree screw thread, an enormous “mega-standardization” triumph that forced others to retool.
• The Consequence: Everything in America adapted. But international incompatibility remained, creating a growing gulf between American-made objects and the rest of the world.

The World at War and the Empire of Screw Threads (15:38–26:19)

• World War II – Incompatibility as Strategic Vulnerability:
  • US and British military hardware couldn’t share screws, bombs didn’t fit bomb racks, bullets didn’t fit guns—total incompatibility was an emergency.
  • US spent $600 million (the cost of 1,000 bombers) just shipping screws, nuts, and bolts overseas to fix this (23:09).
  • A series of Allied meetings (1943–1945) saw the British, under duress, agree to adopt the US 60-degree standard, a “symbolic humiliation.”
• Quote:
  “It’s not just Britain, it’s the entire British Empire. So there’s already a global scale political unit that works on the 55-degree screw thread angle, but also has become newly dependent on the industrial might of the United States.” – Daniel Ammervar (24:08) “This is the British declaring dependence.” – Daniel Ammervar (25:56)

Postwar Ripple Effects—US Standards Become Global Standards (27:48–33:03)

• The Snowball Effect: Once the US and British Empire agreed on the 60-degree thread, other nations had little choice but to conform, given their dependence on American industrial production.
• Rise of International Organization for Standardization (ISO): Founded in 1947 by 25 nations, it formalized global technical standards—often aligning with US practices.
• Examples:
  • The concert A pitch rose from 435 Hz (European standard) to the American 440 Hz (28:33).
  • The familiar red octagonal stop sign began as a US innovation, spread globally—despite initial international standards picking yellow, the US’s late switch to red led the world to follow (29:04–31:32).
• Quote:
  “If you look at where the red octagon currently is adopted as a stop sign, you are looking at countries that account for 91% of the world’s population, including North Korea.” – Daniel Ammervar (31:32)

The Invisibility and Peculiarity of American Power (31:42–36:30)

• A “Soft” Form of Empire: Rather than ruling by force or colonization, the US spread its standards, creating an “invisible empire” felt daily in all industrial societies.
• America as Outlier: Despite foisting standards on others, the US resists adopting the global metric system—a rare case where it declines to compromise.
• Quote:
  “It’s really easy if you grew up in the United States to look around the world and not recognize that all the tailwind is at your back materially, culturally, in so many ways. And everyone else is facing a headwind. I mean, this is a country essentially that was born on Third and thought it hit a triple.” – Daniel Ammervar (36:07)

Reflections on Empire, Change, and the Present (36:30–38:51)

• Historical Amnesia & Modern Threats: Over time, people forget the value of standards and international rules until a crisis reminds them (e.g., recent resurgences of fascism or imperialism).
• Change in Power Projection: There are signs that “hard power” is returning in global affairs, but the softer empire of standards and objects endures.
• Quote:
  “The screw thread is a really good example of how, just in like the most quotidian ways, the United States has, like, colonized the washing machines of India.” – Daniel Ammervar (38:25)

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Notable Quotes & Memorable Moments

• On the need for standards during emergencies:
  “What if your hose doesn’t fit his hydrant? You’ve got a serious problem. The cost of non compliant screw threads… it’s bad enough during peace, it’s horror during war.” – Daniel Ammervar (15:46)
• On the symbolism of technical adoption and subordination:
  “This is the British declaring dependence… in the realm of objects, which turns out to be a really important economically determinative realm, we’re going to take orders from you rather than the other way around.” – Daniel Ammervar (25:56)
• America’s quiet dominance:
  “You don’t need to plant a flag when you’ve already threaded the bolts.” – Roman Mars (35:35)

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Timeline of Key Segments

| Timestamp | Segment | |-----------|---------| | 01:28–03:43 | The Baltimore Fire and America’s pre-standardization chaos | | 04:20–05:42 | The screw thread as civilization’s skeleton | | 06:08–09:17 | Herbert Hoover and the birth of standardization | | 10:42–14:13 | The challenge and achievement of the 60-degree screw | | 15:38–16:59 | Wartime need for compatible standards | | 21:16–26:19 | WWII’s urgency forces Britain’s adoption of US standards | | 27:48–30:16 | Snowballing of US standards globally; stop sign story | | 31:42–36:30 | America’s invisible empire and resistance to metric | | 36:30–38:51 | Modern reflections, changing global power dynamics |

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Conclusion

Through the story of the 60-degree screw thread, the episode reveals how the quiet machinery of standards has built an American-led material world. Herbert Hoover’s technocratic drive catalyzed a process that was cemented during World War II, making US measures and conventions the default globally. This “invisible empire” of objects and protocols continues to hold sway, often unnoticed by those within it, but profoundly shaping life for billions—a subtle, enduring legacy of American power.

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Recommended Reading:
“How to Hide an Empire” by Daniel Ammervar

Produced by: 99% Invisible & BBC Studios | Host: Roman Mars

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Transcript

[Roman Mars]

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[Daniel Ammervar]

In 1904, Baltimore had an enormous fire.

[Roman Mars]

This is historian Daniel Ammervar.

[Daniel Ammervar]

And a fire that was so big and it went on for so long that A it completely overwhelmed Baltimore firefighters, but B it just lasted long enough for Baltimore to desperately call for help from neighboring fire companies.

[Roman Mars]

No one knows for sure how the fire started, but as the fire spread to block after block of Baltimore's downtown, the SOS went out to nearby cities.

[Daniel Ammervar]

So Philadelphia, Annapolis, Wilmington, Harrisburg and the other firefighters rushed to fight the fire. And you know, they had their hoses and they were ready to screw their hoses into the hydrants and get to work. And when they start to do that, they realized that their hoses couldn't screw into the hydrants. There was a fundamental material incompatibility which basically left them completely unable to do anything. And so they just watched as more than 1,500 houses burned in one of the worst fires in US history.

[Roman Mars]

When it was finally put out, one journalist said that the city looked like Pompeii. 80 blocks had burned for 31 hours. The fire highlighted something about 1904 that we don't think about a lot today. The problem with those hoses not fitting was, was kind of the problem with everything. A bushel of greens weighed 10 pounds in North Carolina, 30 in Tennessee. A 50 foot truck leaving Vermont would be 25ft too long to enter Kentucky.

[Daniel Ammervar]

One of the examples I like is football. What we call football in the United States, a national sport. No one agreed what a football was. Different teams had dramatically different size and shapes. Footballs just the central object of football. The football went undefined.

[Roman Mars]

The early 20th century was the wild west for standards. Everywhere you went, things were just defined differently. Before 1927, even traffic lights were different.

[Daniel Ammervar]

In New York, you would stop on green, and it was different in Buffalo. And it just took a while before them to be like, oh, yeah, we should really have the same system in the same city.

[Roman Mars]

Today we all stop at red and go on green. One of the endless standards that is so standard, we don't even think of it as a standard. Now everything we use, every way we travel or place we visit is held together by an agreement about how every tiny detail should be. But landing on those agreements, that took long, protracted fights. Fights between regulators and manufacturers, politicians and lobbyists. And perhaps no fight was as challenging or, or as consequential as the battle over the thing literally holding our world together. The screw thread.

[Daniel Ammervar]

The screw thread is the way in which you achieve metal on metal fastening. And it turns out that the industrial world is full of occasions when you need to fasten one piece of metal or rigid object to another. Like, that's the industrial revolution.

[Roman Mars]

And as industry was taking off in the U.S. the disagreement over the screw thread had become dire. A disagreement whose consequences would spiral out across the world.

[Daniel Ammervar]

So you get these moments where, like, senators will start just talking about, like, the importance of the humble screw thread. I found one who said, the screw thread is a simple device, but it ties together the whole mechanical skeleton of our civilization, which on the one hand seems overblown. But you're like, is it wrong? I don't know that it's wrong.

[Roman Mars]

From 99% Invisible and BBC Studios, this is a history of the United States in 100 objects. I'm Roman Mars. Today, how America used the screw thread to build an invisible empire.

[Daniel Ammervar]

And that little thing, the screw thread is such a potent, hard to notice, but nevertheless deeply consequential symbol of the way in which the United States has remade the world, or the world has had to remake itself to accommodate the United States.

[Roman Mars]

Foreign. Let's fast forward to the 1920s, almost nothing is standardized. The world is still utter chaos. That's barely an exaggeration. But the American government is starting to take the problem seriously. And luckily, there was one particular bureaucrat who was ready to tackle this chaos. Secretary of Commerce Herbert Hoover.

[Daniel Ammervar]

When I had grown up, I had known Hoover to be the president who oversaw the Depression. And I just thought, well, he must have been wildly incompetent. And sure, maybe he wasn't a very good communicator or steward of the country's economic fortunes, but he was a really good bureaucrat, and he was deeply invested. I mean, actually sort of ideologically obsessed with standardization. I mean, at a time when the economy was not the most stable thing and workers were fighting with factory owners, and sometimes that was getting quite violent. You could be on one side of that, you could support the unions. You could be on another side of that, you could be for the bosses. And Herbert Hoover was like, no, no, no, no, no, no. Everyone's screwing this up because we can actually just get a much more efficient economy and squeeze much more juice from the lemon if we just make the objects more efficient. So what a weird technocratic strategy. But he's like, oh, all of these arguments are just about slight profit margins, and we can get far larger ones if we can get everything to be more efficient. And the way to do that is to just draw manufacturers into a room and get them to agree to do things the same way. Because once that happens, everything speeds up and all the friction and the economy goes away. That was his big calling.

[Roman Mars]

Bringing the world of objects into peace and harmony was really a natural extension of who Hoover was. The kind of guy with a cat he named Mr. Cat. The kind of guy who loves to fish, but not just for the sport of it, because it promoted meekness and quieted hate in the soul. The kind of guy who, when he went fishing, he did it in a full suit, a starched collar, tie and jacket under his waders.

[Daniel Ammervar]

So you're like, he dressed up for the fish. Oh, my God, what a respectful man. Lovely guy.

[Roman Mars]

So lovely. Unless you try to bend the rules. Once, when Hoover was younger, he was manning the ticket booth at a college baseball game and found himself face to face, face with former President Benjamin Harrison.

[Daniel Ammervar]

And Herbert Hoover won't let him in because he doesn't have a ticket. Like, this is. This is a guy who believes in the rules. Yeah, that's right. He believes in the system.

[Roman Mars]

But Hoover had his work cut out for him because getting everyone to agree on what that Standard should be was nearly impossible.

[Daniel Ammervar]

Standards are a funny thing because everyone wants to be on the same page, but no one wants to have to do that by getting onto someone else's page. And the more these industries develop, the more each corporation is invested in their own world. There was just a lot of physical retooling that would have to be done. So you would lose a lot of capital if you had to suddenly start making things the way that your competitor made them rather than the way that you were accustomed to make them.

[Roman Mars]

Because not only would you have to retool, in the process of retooling, your competitor is continuing to sell and develop and manufacture things while you're waiting for your screw thread to conform to some kind of standard.

[Daniel Ammervar]

And in all that time, your competitor is going to try to snap up all your business.

[Roman Mars]

But do not worry your pretty little heads. Herbert Hoover has a plan, a calm, well reasoned plan.

[Daniel Ammervar]

So his move is not to pass laws. His move is just to get the manufacturers to agree. And apparently he's shockingly persuasive in doing so. So as commerce secretary, he pulls in the manufacturers of paving bricks and it's like, okay, there are 66 kinds of paving bricks, which is altogether too many. Can there be fewer? Well, there can. And actually paving brick is relatively easy because it's just dimensional. So after talking to Herbert hoover, there are 11 kinds of paving brick. But like, that's the easy round. He just keeps going. It is everything. So standards for lumber, cement doors, steel bed springs, mattresses, hospital linens, ball bearings, brake linings, and then like, just things that you don't think need standards. Do glass tumblers need to be standardized? Not necessarily in their shape, but how many hours of boiling water can they withstand in order to be sold as glass tumblers? Six is the answer. Okay, there was an answer to that question. What percentage of new rubber on their treads must tires have? 70%. It's just like everything. Every standard, every specification, that's the world that Herbert Kruger is trying to make.

[Roman Mars]

So of all these things, one great challenge was the humble screw.

[Daniel Ammervar]

Yeah.

[Roman Mars]

So could you talk about this is a challenge and what we're dealing with here. When it comes to a screw, you

[Daniel Ammervar]

have to think of the standardization of the screw as a kind of mega standardization. So if you're standardizing hospital linens, that's an issue for hospital linen producers. If you're standardizing the screw, that's everyone. Screws are in everything. And even if you're producing an object that doesn't have screws in it like hospital linens. You're doing it with a machine that requires screws.

[Roman Mars]

Lets zoom in on how the screw works for a second. The thing that makes the screw hold two objects together is the screw thread, that raised ridge that's wrapped around the cylinder. That thread has a particular angle which used to be different in different screws.

[Daniel Ammervar]

The variation is not easily visible to the eye. You wouldn't look at a 55 degree screw thread angle and think it looks hugely different from a 60°1. The difference is everything. The difference is absolutely everything.

[Roman Mars]

The angle of the screw thread has to match the angle of the groove inside the object it's going into in order for it to work. And you can't really tell if a screw is going to fit into something until you try it. And more and more that was becoming everyone's problem. Like the scale of this isn't just like people agreeing on a thing who are muckety mucks and bureaucrats in different states or whatever and coming up with legislation. This is literally every person who makes a machine and every machine that makes a thing has to agree on this.

[Daniel Ammervar]

Yeah, yeah.

[Roman Mars]

These are tiny, tiny people like who maybe have one machine in their whole factory.

[Daniel Ammervar]

Yeah, that's right. And then you also think that like basically it's a whole world that has to be reconstituted. Like okay, if you have a machine in your factory that is with a now non compliant form of screw thread, all those spare parts that you, you have to buy them anew.

[Roman Mars]

So there's this recognition that getting a standardized screw needs to be done and at some point they achieve it. When did that happen?

[Daniel Ammervar]

That happens in the 1920s. It happens under Hoover. And it's really hard because it's one thing to get the paving brick manufacturers in a room, but to deal with a screw thread problem, that's everything. Screws are in everything. And again, it's one of those really tricky things. Everyone wants there to be a standard. No one wants to lose out. They don't want it to be someone else's standard. So Herbert Hoover works his extraordinary magic and in 1924 there is a national screw thread standard. And Hoover, I just imagine him feeling like the moment of his greatest triumph in this bureaucrat's life. He says, now the half inch nuts screw on to all the half inch bolts. What a dream. Utopia is ours.

[Roman Mars]

Put yourself in Hoover state of mind here. If you could like you have a screw with you. Like what do you see when you see this? If you're Herbert Hoover.

[Daniel Ammervar]

Yeah. So if you're Herbert Hoover, the thing that you're the most locked in on is the screw thread angle. And so the screw thread angle that the United States agrees on is the 60 degree angle. That's a huge achievement. But that means every other screw thread no longer works at all.

[Roman Mars]

So this consortium sort of agrees. Now this published standard happens, this consortium people vaguely agree. They begin to make their things in this 60 degree threading. This solves the problem of the US. This is a huge achievement in and of itself. But this is not what happened necessarily in the rest of the world. So what's going on in the rest of the world in terms of screw threads and things like this?

[Daniel Ammervar]

It's exactly the same thing. But you have to imagine that all of the kind of anarchy that the United States was experiencing locally is actually even worse on a global scale. The early 20th century is a time of rapid pace technological development. And every year that there's just more stuff being made, it starts to matter more how it's made and whether the objects can speak to each other. I think language is a really good metaphor here. What you have to imagine is that the United States is producing a growing world of industrial objects that all speak 60 degrees. And then when those objects venture out into the world, they encounter a world of foreign objects that, I mean, it's not even a language that's commensurable. It's not even a language that's comprehensible. They're just like, oh, you speak 55 degrees? We will never talk. There's nothing for us to talk about. I don't know what you're saying. We can never have any relationship with each other.

[Roman Mars]

But then World War II came along and demanded that we have a very real screw based relationship with the rest of the world.

[Daniel Ammervar]

So there's this famous moment when FDR is trying to explain why, despite the fact that World War II has not yet hit the Americas, the United States should actually be deeply interested in this war and in fact might need to participate in it, if not fighting, at least by supplying material. And so the way he puts it is, suppose my neighbor's home catches fire and I have a length of garden hose. If he can take my garden hose and connect it up with his hydrant, I might help him put out his fire. And I mean, I'm a historian, I've seen that line like many, many times. And it's always about being a good neighbor. But then when you think about it, you're like, wait a minute, you imagine yourself as Herbert Hoover and you just imagine yourself like kind of raising your hand in the back of the room and being like whoa whoa whoa whoa whoa whoa. What if your hose doesn't fit his hydrant? You've got a serious problem. And the cost of non compliant screw threads. It's bad enough during peace, it's horror during war.

[Roman Mars]

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[Daniel Ammervar]

So World War I was fought with horses. World War II is much more mechanized war. In fact, one of the main ways in which the United States participates in World War II is essentially acting as quartermaster to the world as supplying stuff to all of its allies. It outsources the fighting to other countries and it just sends its factories into overdrive. The problem that everyone recognizes at the start of the war is that none of the US Stuff plays with the foreign stuff. So there's a Canadian official who just says, look, you have to understand that at the start of the war, there is not a single gun or a single round of ammunition that can be shared among the Allies. The bullets are slightly different sizes, and so one bullet doesn't fit another gun. The US Bombs do not fit the UK bomb racks. And that sounds like a small thing, but, like, try dropping a bomb. If the bomb doesn't fit on the bomb rack, you drop it with your hands. Yeah, you'll drop it, but not in the way you want it to.

[Roman Mars]

And of course, there's a huge problem with the screws. They're in the weapons, tanks, and planes, which all have to work in faraway places.

[Daniel Ammervar]

So, like, think about setting a jeep. So that's a thing that happened a lot. The United States was setting Jeeps all over the world. And first of all, it's inefficient to ship a Jeep. So what you want to do is you want to do the IKEA method, and you want to ship parts of a Jeep. But that means you have to have people on the other end who can put the Jeep together okay. So that's fine. But then, you know, the Jeep's, of course, going to break, and it's going to break down in all kinds of ways. So that means you have to have, on the other part of the world, people who know how to work with that Jeep. And they have all of the parts that allow them to repair the jeep. And you need that in dozens of countries all at the same time.

[Roman Mars]

The design, construction, and repair of everything that the army had to have to survive the war all relied on screws that often just didn't fit. Throughout the war, the US spent $600 million shipping extra screws, nuts, and bolts overseas to deal with the incompatibility issues. $600 million on screws. That's enough money to build 1,000 B29 bombers. So in the middle of this war, there's a meeting to try to solve some of this problem, because the British recognize that they need to sort of get onto the. Could you talk about that?

[Daniel Ammervar]

Yeah. So, I mean, first of all, it's amazing in some ways that in the middle of the war, while the British are literally being bombed, they're debating about screw thread standards. But of course they're debating about screw thread standards, because if you don't work this out, the whole thing comes grinding to a halt. Like Herbert Hoover's point that incompatibility of standards is a massive inefficiency. I mean, that just sounds like a dorky thing to say, but it turns out if you're in the middle of a war, inefficiencies are lethal. And so you really do want to resolve the screw thread issue. Now, Britain operates on a 55 degree screw thread, so they don't speak to each other. And it's not just Britain, it's the entire British Empire. So there's already a global scale political unit that works on the 55 degree screw thread angle, but also has become newly dependent on the industrial might of the United States. And so there are a series of Anglo US meetings between 1943 and 1945, and I just sort of went through them all and what you can see is the formerly proud world dominating British just being humbled and chastened and eventually completely given up. So the first meeting they have, meeting one, they say, we would be willing to talk about screw thread standardization. Okay, interesting. Okay, let's have that conversation. Second meeting they say we would agree to consider retooling. So the screw thread standardization would happen by us adopting your screw thread is something that we would consider. In the third meeting they say, okay, we are retooling, but it is just temporary. It is just for the purposes of the war. Don't think that you own us. In the fourth meaning they just say, okay, we are now on your screw thread standard. Wow. Wow.

[Roman Mars]

I suppose if you're in a negotiation, it helps to have the person you're negotiating with being bombed.

[Daniel Ammervar]

Currently, bombs are literally dropping on London as they're working all this out. Yeah.

[Roman Mars]

This moment, the UK agreeing to adopt the US screw thread is a huge win for the US for one, retooling everything, all the weapons and planes and jeeps, that's expensive.

[Daniel Ammervar]

And then I think on top of it, you have to see the symbolic humiliation. You know, it's one thing for the United States to declare independence. This is the British declaring dependence. This is the British basically saying that in the realm of objects, which turns out to be a really important economically determinative realm, we're going to take orders from you rather than the other way around.

[Roman Mars]

We benefited greatly from World War II not happening on our shores.

[Daniel Ammervar]

Totally. Yeah. Yeah. So yeah, just like, just think about World War II from a military perspective. First of all, it's happening at a moment of enormous technological dynamism. So the kinds of things that can be produced after the war compared to the kinds that could be produced before are barely recognizable. Just, even just the war itself is a time of great invention. And all of those inventions are going to nudge the globe toward a more united, technologically interdependent configuration. And then the war accelerates that tremendously. A single country right at the end of the war is producing some 60% of all of the industrial products of the world is diplomatically dominant. And it got really lucky. And you're right, every other country's factories are bombed out, and the United States factories are going strong and in fact, going stronger than they've ever been. So you just have to gape at the shocking good fortune that this country has to have been in this position. Not just where it was, but when it was. Yeah.

[Roman Mars]

But also like, you know, to give Hoover his props. You know, good fortune lands on people who are prepared.

[Daniel Ammervar]

Yeah. Like, Hoover saw it coming.

[Roman Mars]

And then when does the rest of the world begin to conform?

[Daniel Ammervar]

So once you have the United States and the British Empire on 60 degrees, it just. I mean, this is the way standards work. They snowball. You know, if there's like a few evenly matched parties and they're all doing different things, you can imagine any standard prevailing. But if you're in a world where most people do things one way, then it's in your interest not to fight it. It's in your interest to just quickly retool, to get with the winning team as soon as possible. And so the whole world is so materially dependent on what US factories are putting out that the world has to adjust. And so the US standard prevails in so many different realms, big and small, visible and invisible. US standards just absolutely dominate the field.

[Roman Mars]

Right after World War II, in 1947, delegates from 25 countries created the International Organization for Standardization, a kind of united nation for things. And object by object, standard by standard, the world started tuning itself to the United States. And I mean that literally. Europe had always defined a concert, a note as 435Hz, but the US's slightly sharper, 440Hz won out. And that was just the beginning.

[Daniel Ammervar]

My favorite example is the stop sign. So what should a stop sign be? It's completely arbitrary. Right. We're used to them being red and octagonal, but they don't have to be. So what's the story with a stop sign? So the US is advanced in auto manufacturing, so it adopts a stop sign early. And it's just a local stop sign. So there's a square stop sign. And a Detroit cop is like, square is not screaming stop to me. So he clips the corners off, making it octagonal. And he's like, okay, well, that's clearer. Has a more obvious visual identity. And then so the United States form of Stop sign proliferates in the United States. And then in 1953, so not too far after World War II, there's an international standard for stop sign which adapts the US yellow octagonal stop sign as a standard. And if you're hesitating this moment being like, wait, yellow? That's because the US stop signs were yellow

[Roman Mars]

in 1953. The American stop sign was a yellow octagon. And the rest of the world just got on board.

[Daniel Ammervar]

All the countries are like, okay, like, to the degree that you can have your stop signs be yellow octagons, that would make it a lot easier to travel from country to country if we all kind of agreed what a stop sign looked like. And then the next year, 1954, industrial chemists in the United States develop a durable reflective red finish. And traffic engineers are like, red would be better. Red would be better. It would match the traffic lights. That's a good idea. So the US despite the whole world having just agreed to do the yellow octagon, US Is like, we're going to do red octagons now. And so the US Just starts doing red octagons. And like, you just have to imagine the, like, unbridled fury of traffic engineers, like, worldwide as they're like, oh, God, we just did yellow. You know, and then eventually the world just catches up and does red. Because to play by a different system as the United States is going to be to court chaos and in this case, traffic accidents. And I had a research assistant, we worked together to like run the numbers. And I think this is true. If you look at where the red octagon currently is adopted as a stop sign, you are looking at countries that account for 91% of the world's population, including North Korea. Wow.

[Roman Mars]

So not only are we feeling ourself and our power in this moment of getting the standardization to make a better world, we're kind of like a mad king.

[Daniel Ammervar]

Capricious Joffrey wants to stop signs to be read. Yeah, yeah, yeah. And you have to understand the power as cutting in two distinct ways. So on the one hand, the things that the United States wants for itself get adopted assiduously by other countries just as a way of surviving and having economies that work. On the other hand, the United States, unlike other countries, has the power to defy international standards. And so the clearest example of this is the metric system. So, I mean, one of the really extraordinary forms of standardization that happens globally is the internationalization of the metric system. That is a France centered operation. And it happens before the United States comes of industrial age. But the United States is so powerful that it, not totally alone, but nearly alone among countries, feels no compulsion to adopt the metric system. So it's just like, yeah, we work in pounds and inches, deal with it. And so that's how you get a world where for most people on the planet, football is a FIFA sport on a hundred meter pitch and for the United States, Football is an NFL sport on 100 yard field. The United States is on the one hand foist its standards on everyone else, on the other hand feels no obligation to adopt the rest of the world's standards.

[Roman Mars]

At the end of World War II, the US had so much power, military bases and fleets across the world, one of the only functional industrial economies left standing, that it could have gone full old school empire, colonies, territories, the whole Victorian playbook. But Daniel says the fact that we didn't isn't because of some grand moral awakening. It was because we stumbled on something better. What is so kind of remarkable and novel about this form of imperialism is just like how much effort the old form took of like putting troops in places and leaving them there. And then you have some kind of governor who lives there with a staff and puts down insurrections and things like this. And you know, there's obviously elements to force power and active power and US domination, but it's kind of a new novel form. Do you think that the war and the adoption of the US standard change the nature of imperialism and colonialism?

[Daniel Ammervar]

Yeah, we used to live in. I mean, it's tricky because things might change in the 21st century and it feels like they're changing very quickly, even in 2026 this year. But it used to be the case that projecting power involves claiming lots of territory, fighting wars of pacification to do so, and then bumping up against your imperial rivals and fighting wars with them. Maybe World War I was like that, World War II was like that too. And it seems like in various ways the United States has Huns, new ways of doing what it wants in the world. It's not free of force and it's not even free of territory. The United States has like hundreds of military bases around the world. But when it comes to things like the screw thread, you're absolutely right. Like those aren't handled at the point of the gun. It is true that historically empires have put a lot of energy and a lot of coercion into, I don't know, getting people to speak English or speak French or speak Dutch. That's not easy to do. But the United States has, during a period of globalization, has been, and particularly was at the start, so just enormous that it acquired a gravitational force that allowed the United States to achieve a lot of things that empires have sweated to achieve in the past.

[Roman Mars]

This empire building was made possible by the new screw thread, that tiny thing, and all the invisible standards it represented, expanded the rules of power. It turns out you don't need to plant a flag when you've already threaded the bolts.

[Daniel Ammervar]

A lot of US Power happens on an almost subterranean level. There's a lot of privileges that the United States enjoys vis a vis the world. They're totally visible to people outside of the United States, but often invisible to people in the United States. You know, it's not the only kind of power, and it certainly uses its military all the time. But it's really easy if you grew up in the United States to look around the world and not recognize that all of the tailwind is at your back materially, culturally, in so many ways. And everyone else is facing a headwind. I mean, this is a country essentially that was born on Third and thought it hit a triple. Yeah, yeah.

[Roman Mars]

So like many things in the world today, there's been a long enough distance that we have sort of. It sort of takes two generations, it seems. Maybe you can correct me as a historian, but there's sort of like two generations of like not having fascism that people go, oh, what about fascism? You know, or like, what about imperialism? Or what about no vaccines or something? Like, they forget what it's like to have polio, you know, and our kind of. There's a new kind of threat of an old fashioned imperial expansionism.

[Daniel Ammervar]

That's right.

[Roman Mars]

How are you perceiving this? As somebody who like wrote about this as being a subtle thing that America did to it, becoming a more overt thing.

[Daniel Ammervar]

Yeah. I was really interested in the smooth functioning of US Power. And what I didn't see was a willful return to the rough exertion of U.S. power. We've had a decades long relief from the kind of border crossing, large scale imperialist warfare that marked the 19th and early 20th centuries. And that was really helpful in two ways. That spared us a lot of the wars of pacification which came with colonialism. And it also spared us the conflicts of imperial rivalry, both of which turn out to be really dangerous forms of warfare. And I'm not saying we've been free of wars, but a lot of the conflicts have been civil in nature. And it seems like we. Not just through Trump, but through Putin as well. It seems like we may be headed back to a different way for countries to project their power. And if that's true, it's going to be really dangerous because a, it's all the old kind of violence, but b now with nuclear weapons, of course, even

[Roman Mars]

if the world returns to an old form of conquest, this quieter form of power isn't going anywhere. America is already all the time expanding its empire.

[Daniel Ammervar]

And so the Screw thread is a really good example of how, just in like the most quotidian ways, the United States has, like, colonized the washing machines of India. You know what I mean? Like, just like in all these little ways, the mark of the United States is already everywhere, all over the world.

[Roman Mars]

Daniel Amavar's truly excellent book is how to Hide an A History of the Greater United States States. A History of the United States in 100 Objects is a production of 99% Invisible and BBC Studios. It's hosted and curated by me, Roman Mars. Our series producers are Priscilla Alabi, Brenna Dahldorf and Ellie Lightfoot. Our associate producer is Isaac Fisher. This series was edited by Annie Brown and Courtney Harrell, mixing by Charlie Brandon King, Fact checking by Amy Bracken. Our theme song is by Swan river from 99% Invisible. Our executive producer is Kathy Tu from BBC Studios. Our executive producers are Annie Brown and Courtney Harrell. Our production coordinator is Shan Pillay and the production manager is Mabel Finnegan Wright. Artwork by Stephen Lawrence. 99% Invisible is part of the Sirius XM podcast family, headquartered in beautiful uptown Oakland, California, and BBC Studios is headquartered in beautiful white city West London. If you want to get in touch or have an object for us to consider, email us at 100objects99pi.org.

[Daniel Ammervar]

And Doug, there's nowhere I wouldn't go

[Roman Mars]

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[Daniel Ammervar]

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[Roman Mars]

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[Daniel Ammervar]

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[Roman Mars]

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[Daniel Ammervar]

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[Roman Mars]

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[Roman Mars]

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