In 1793, noted French scientist Joseph Dombey departed Le Havre, France bound for Philadelphia. His mission was to meet with Thomas Jefferson and give him two of the rarest items on Earth. Unfortunately for Dombey, fate had other intentions and storms pushed the ship he was aboard well of course. And so it was that around the time he was supposed to deliver his precious cargo to Jefferson, he found himself instead at the mercy of British pirates. Being French in this situation wasn’t exactly ideal, so at first he attempted to pass himself off as Spanish, but his accent gave him away. Dombey was eventually taken to the small Caribbean island of Montserrat where he ultimately died before he could be ransomed.

So what was the precious cargo he was to have delivered as a gift to the United States? Two small copper items (of which only six sets existed on Earth at the time) — standards representing a meter and a grave, the latter better known today as a kilogram.

At the time, the United States, having already become one of the first nations in the world to adopt a decimal, base ten system for currency was strongly considering doing the same with the system of weights and measures to get rid of the hodgepodge of British weights and measures system mixed with others also commonly used throughout the young nation. Thus, with the initial strong support of then Secretary of State Thomas Jefferson, and thanks to a desire to continue to strengthen ties between France and the United States, adoption of the new French metric system seemed close at hand. Along with a trade agreement concerning grain export to France, Dombey was to deliver the meter and grave standards and attempt to argue the system’s merits to Congress who, at the time, were quite open to adopting these units of measure.

Thomas Jefferson.

(Rembrandt Peale)

Of course we all know how this turned out — Dombey never got a chance to make his arguments and thanks to concerns about whether the metric system would even stick around at all in France, combined with the fact that trade between Britain and the U.S. would be hindered by such a change, the U.S. eventually decided to abandon efforts to adopt the metric system and mostly stuck with the British system, though the U.S. Customary Units and what would become the Imperial System would soon diverge in the following decades.

But as more and more nations came to adopt this new system of weights and measures, the U.S. slowly began to follow suit. Fast-forwarding to 1866 and with the Metric Act the U.S. officially sanctioned the use of the metric system “in all contracts, dealings or court proceedings” and provided each state with standard metric weights and measures. In 1875, the United States was one of just 17 nations to sign the “Treaty of the Metre” establishing, among other things, the International Bureau of Weights and Measure to govern this system.

Fast forward a little under a century later and the full switch seemed inevitable in the United States after the 1968 Metric Study Act. This ended up being a three year study looking at the feasibility of switching the United States to the metric system. The result? a report titled A Metric America: “A Decision Whose Time Has Come”recommending the change and that it could be reasonably done in as little as 10 years.

Unfortunately, the public was largely either apathetic or strongly opposed to making the switch. (According to a Gallup poll at the time, 45% were against it.) This was nothing new, however. A huge percentage of the time a given people of a nation have been asked by their government to switch to the International System of Units, the general public of those nations were largely against it, even France itself, who went back and forth for decades on the issue, contributing to the United States’ hesitation to adopt it in the early going. Brazil actually experienced a genuine uprising when the government forced the change in the late 19th century. Over a half century later, British citizens still stubbornly cling to many of the old measurements in their day to day lives, though have otherwise adopted SI units.

So why did all these governments frequently go against the will of their people? Arguments for the economic benefits simply won out — as in so many matters of government, what businesses want, businesses often get. So the governments ignored the will of the general public and did it anyway.

But in the U.S. the situation was different. Not having the pressure from being bordered and economically as bound to one’s neighbors as in Europe, and being one of the world’s foremost economic powerhouses itself, the immediately economic benefit didn’t seem so clear. For example, California alone — one of 50 states — if it were its own nation would have the 5th largest economy in the world. Texas and New York state aren’t far behind when compared to nation’s of the worlds economies at 10th and 13th respectively, let alone the other 47 states.

Seeing lesser readily apparent economic benefit, and not having the same geographic pressures as in Europe, in the 1970s many big businesses and unions were in strong opposition to the change, citing the cost of making the switch and, on the latter side, unions worried that such a change would make it easier to move jobs that formerly used customary units oversees, given that now such product could more easily be purchased from abroad.

Swayed, when the 1975 Metric Conversion Act was signed by President Gerald Ford, it had largely lost its teeth. While it did establish a board whose job it was to facilitate the nation’s conversion and put forth various recommendations, the act did not have an official timeline and made the switch voluntary.

Nevertheless, contrary to popular belief, in the decades since, the United States actually has largely switched to the metric system, just the general public (both domestic and international) seem largely ignorant of this. The U.S. military almost exclusively uses the metric system. Since the early 1990s, the Federal government has largely been converted, and the majority of big businesses have made the switch in one form or another wherever possible. In fact, with the passage of the Metric Conversion Act of 1988, the metric system became the “preferred system of weights and measures for United States trade and commerce”.

In the medical field and pharmaceuticals. the metric system is also used almost exclusively. In fact, since the Mendenhall Order of 1893, even the units of measure used by the layperson in the U.S., the yard, foot, inch, and pound, have all been officially defined by the meter and kilogram.

Speaking of the general public side, nobody in the U.S. blinks an eye about food labels containing both metric and customary units (required thanks to the Fair Packaging and Labeling Act, with the majority of states since also allowing metric only). The gram is commonly used to measure everything from the amount of flour to add in a recipe to how much marijuana one buys from a shop or, where it’s still illegal, their local dealer. And if you were to ask someone to pick up a two liter of Dr. Pepper or how a person did running a 10K, most everyone in the United States would know exactly what you are talking about. Beyond this, you’d be hard pressed to find a ruler in the United States that doesn’t include both inches and centimeters and their common divisors.

Further, in school, both customary units and the metric system are taught. Yes, while Americans may generally have little practical need to learn a second language, most are, at least for a time, reasonably fluent in two very different systems of measurement.

As with languages unpracticed, however, once out of school, many lose their sense of the latter from lack of use and concrete perspective. It’s one thing to know what 100 and 0 degrees Celsius refers to with respect to water, it’s a whole different matter to “get” what temperature you might want to put on a jacket for. However, students who go on to more advanced science classes quickly pick up this perspective as they become more familiar and, thus, the scientists of America aren’t at the slightest disadvantage here, also contrary to what is often stated in arguments as to why the U.S. should make the switch a bit more official than it already is. All students that go along that path become just as familiar as their European brethren, if a little later in life.

(Photo by Tamarcus Brown)

This all brings us around to why the United States hasn’t made the switch to the metric system more official than it already is. Primarily three reasons — cost, human psychology, and, at least on the general public side, little readily apparent practical reason to do so.

As to cost, while there has never been a definitive study showing how much it would cost the United States to make the switch official and universal, general estimates range even upwards of a trillion dollars all things considered. Why so high?

To begin with, we’ll discuss a relatively small example in road signs. Installing street signs is an incredibly expensive affair in many places for a variety of reasons. For instance, in 2011 the Washington State Department of Transportation claimed it costs anywhere from ,000 to ,000 PER SIGN, though they later clarified those were worst case and most expensive scenarios and sometimes the signs and installation can ring in ONLY around ,000. Bronlea Mishler of the DOT explains,

Installing a sign along a highway isn’t quite as simple as pounding some posts into a ground and bolting on a sign — that’s why the cost is so variable. There are two ways to replace a sign. One way allows us to install it under old rules; the second way requires us to follow new federal standards… The old rules apply if we are just fixing something, not building something new. Installing a sign alongside the road counts as fixing something — basically, just giving drivers more information. If we install a sign on the side of the road, it would cost: ,000 to make the sign, buy the beams and rivets; ,000 for two steel posts and concrete; ,000 to clear brush and other landscape work before and after installation; ,000 for maintenance crews to set up traffic cones, work vehicles, program highway signs and spend the evening doing the work. Total: ,000…. The new rules apply if we’re doing a new construction project. Costs would be higher because we would have to bring everything up to the current highway code. These often involve putting up a sign bridge, a steel structure that spans the entire freeway to hold up multiple signs. Typical costs include: ,600 to make the sign, buy the beams and rivets because the sign must be bigger; ,000 for the sign bridge. Total: ,600.

WSDOT Deputy Regional Administrator Bill Vleck also stated, beyond many of these signs needing to be special ordered on a 1-off variety (think a highway sign with city name and distance marker) and often being much larger than most sign makers make, drastically increasing cost, some of the seemingly exorbitant costs are due to special features of the signs few know about. For instance, Vleck states, “If there’s an auto accident, if a car hits that sign post and there’s any kind of injury involved, the state is going to be liable, so we’re looking potentially at a multi-million dollar settlement in those kind of situations… [So] it would have to be a breakaway type sign post, and it has to be specially fabricated so that if a car hits that sign, it reacts appropriately and doesn’t come down and basically take out the occupants.”

For your reference here, in 1995, it was estimated that approximately 6 million signs would need changed on federal and state roads. On top of that, it was noted that approximately just shy of 3 million of the nations about 4.2 million miles (6.8 million km) of public roads are actual local, with an uncertain number of signs in those regions that would need changed.

That said, the rather obscene costs quoted by the aforementioned Washington State DOT would likely be grossly overestimated on a project such as this, with prices massively reduced if special laws were passed to remove much of the red tape, and given the extreme bulk orders that would be called for here, including for the signs themselves and contracts to dedicated crews to make this happen as fast as possible.

For example, in 1995, Alabama estimated they could swap out all the signs on federal highways for a mere per sign (0 today) on average.

(Photo by Ludovic Charlet)

Perhaps a better rubric would be in looking at Canada’s switch, swapping out around a quarter of a million signs on their then 300,000 miles (482,000 km) or so of road. The total reported cost? Only a little over million (about million today) or around 4 per sign in today’s dollars.

Extrapolating that out to the minimum 6 million signs would then run approximately id=”listicle-2635564449″.5 billion + whatever additional signs need swapped out on the 3/4 of the rest of the roads not accounted for in that 6 million sign estimate. Not an insignificant sum, but also relatively trivial for the U.S. taxpayer to cover at about per person + some uncertain amount for the local road signs that need changed.

Moving on to far greater expenses — industry and wider infrastructure.

While it’s impossible to accurately estimate the cost of such a change to American businesses as a whole, we do get a small glimpse of the issue when looking at a NASA report studying the feasibility of swapping the shuttle program to full metric. They determined the price tag would be a whopping 0 million for that project alone at the time, so decided it wasn’t worth the cost for little practical benefit… Now extrapolate that out to the approximately 28 million businesses in the United States, their software, their records, their labels, machinery, employee training, etc. needing switched like some sort of Y2K event on steroids. Thus, while it’s impossible to know for sure, many posit the cost could swell into the hundreds of billions of dollars, if not even creep into the trillion territory — in theory at least.

At this point, even the most ardent supporter of the metric system in the United States may be rethinking whether it would be worth it to make the switch more official than it already is. But don’t fret metric supporters the world over!

To begin with, the raw cost of making the switch doesn’t actually tell the whole story here. In fact, it tells a false story — while the gross total of making the change would be astronomical, it turns out the net cost likely wouldn’t be much, or anything at all.

You see, beyond it noted that, for example, on average Australian businesses saw a 9-14% boost directly attributed to the switch when they made it, back in the United States when companies like IBM, GM, Ford and others spent the money to make the change, they universally found that they made a profit from doing this. This was largely from being able to reduce warehouse space, equipment needs, streamline production, lower necessary inventories, as well as taking the opportunity to, at the same time, remove inefficiencies that had crept into their respective businesses with regard to these systems. They were also able to more uniformly manage their businesses abroad and domestic to the same standards and systems. As a very small example, GM reported they were able to reduce its number of fan belts they had to manufacture and stock from about 900 sizes to 100 thanks to everything that went into the switch.

In some cases the businesses also noted new international markets opening up, both in sales and ability to more easily, and often more cheaply, acquire product abroad. All of this resulted in a net profit extremely quickly from investing the money into making the switch.

(Photo by Fleur Treurniet)

As you might expect from these types of benefits, an estimated 30% of businesses in the United States have largely already switched to metric.

Granted, these are generally larger companies and various small businesses dealing mostly locally might not see such a benefit. However, with the increasing globalization of supply chains, many small businesses would likely still see some benefit.

Unfortunately, particularly when it comes to construction, that general industry has lagged well behind others in switching, and, as you might imagine, the existing infrastructure of the nation from roads to bridges to homes to drill bits to screws to the architectural plans for all of it being based on customary units would not be cheap to change and it isn’t clear here what the net cost would be. However, as in all of this, the cost could potentially be mitigated via a slow phaseout approach with grandfathering allowed, similar to what other nations did, though in most cases on a vastly smaller scale than would be seen in the United States.

All this said, we here at TodayIFoundOut would like to posit that what the international community actually finds irksome about the United States not using the metric system is not United States businesses who deal abroad or United States scientists or even the government — all of which largely use the metric system and all of which have little bearing on what Pierre sitting in his mother’s basement in France is doing at a given moment.

No, what upsets Pierre is that the U.S. general populace does not use the metric system in their day to day lives. Why is this irksome? Beyond just the human drive for uniformity amongst one’s community, in this case of the global variety, because English websites the world over, keen to get some of those sweet, sweet U.S. advertising dollars, cater to the U.S. audience and use the units that said audience is more familiar with, those not familiar are often left to Google a conversion to the units they are familiar with. The alternative is for said websites to include both, but that often makes for a break in the flow of the content, something we here at TodayIFoundOut regularly wrestle with finding a proper balance with.

This brings us around to the human side of the argument. To begin with, while the United States would unequivocally see many benefits to joining the rest of the world in some good old fashioned metric lovin’, as you might expect given the lack of immediately obvious benefit to the layperson, few among the American public see much point. After all, what does it really matter if a road sign is in kilometers or miles, or if one’s house is measured in square feet or square meters?

While some cite the benefits of ease of conversion to other units in a given system, in day to day life, this is almost never a thing that’s cumbersome in the slightest. If it was, Americans would be clamoring to make the change. The argument that ease of conversion between units should be a primary driver for the public to want the change simply doesn’t hold water in an era where, on the extremely rare occasion people actually need to make such a precise conversion in day to day life, they have little more than to say “Hey Google”. And in most cases, even that isn’t necessary when you’re reasonably familiar with a given system.

(Photo by Makarios Tang)

Perhaps a poignant example of how, when you’re familiar, a non base 10 system of measure really isn’t that complicated to deal with in day to day matters, consider that the world still uses 1000 milliseconds in a second, 60 seconds in a minute, 60 minutes in an hour, and 24 hours in a day. What few realize about this is that the original metric system actually attempted to simplify this as well, dividing the day into 10 hours, with 100 minutes in each hour, etc. Unfortunately, most people didn’t see the benefit in switching when also factoring in having to swap out their existing clocks. Nobody has much seen a need to fix the issue since, not even the most ardent champion of the metric system for its ease of conversions compared with imperial or customary units.

And while you might still be lamenting the stubbornness of Americans for not seeing the genuine benefits to themselves that would likely be realized here, we should point out that virtually every nation in the world that uses the metric system has holdover units still relatively commonly used among laypeople that aren’t metric, for simple reasons of not seeing a reason to stop, from calories to horsepower to knots to lightyears and many more. Or how about, have you ever flown on a plane almost anywhere in the world? Congratulations, you’ve in all liklehood unwittingly been supporting the use of something other than the metric system. You see, the pilots aboard, from French to American, use a feet based, Flight Level, system for their altitude, and knots to measure their speed. Just two standards that, much like the American public and their road signs, nobody has seen much practical reason to change.

Now to more concrete human psychology for not making the switch, which has gradually been converting more and more Americans from general apathy to the anti-switch crowd as the decades pass — when one group of humans tells another group what to do, occasionally using terms like “idiot units” and starting flame wars in comments of every website or video posted on the web that uses or discusses said units- you will universally get resistance if not outright hostility in response. This is not an American thing, as so often is purported- this is a human thing.

Try forcing the French government to mandate by law that French is dead and English is now to be universal spoken for the sake of better international trade, economics, and relations. You might argue that in a not insignificant percentage of the world English is already the standard in such international business dealings, but that is really little different than the current situation in business in the U.S. concerning the metric system. What we’re talking about is how the general populace of France would react if the government mandated such a change, and even more so if outside nations were pressuring it. Again, it’s not an American thing — it’s a human thing.

Beyond that, as anyone whose ever done anything online is well aware of — humans hate change. Loathe it. Make any change to, say, a format or style of video, no matter how small, and rest assured no matter if the change is unequivocally vastly superior and the audience universally comes to agree with that, a not insignificant number of one’s audience will complain, sometimes vehemently, at first. More directly we see this again and again throughout the history of various nations making the change to SI. Again, resistance of change is not an American thing — it’s a human thing.

(Photo by patricia serna)

But fret not world. You see, slowly but surely the United States has been converting to metric and, for most practical purposes for those outside of the United States, other than having to see it on websites (which, again, we posit is the real driver of people’s ire the world over), the switch has already been made. So much so that at this stage while the cars made in America may say miles per hour on the speedometer, the makers of those cars are using metric to measure and build the things. The very military that defends American’s right to use “Freedom Units” has long since largely converted to the un-free variety.

In the end, money talks, and, for much the same reason other big holdouts like the UK ultimately gave in, as American businesses who have interest in dealing internationally continue to make the switch, they are seeing to it that the metric system more and more creeps into the daily lives of Americans. This will only continue until the inevitable complete adoption. Slowly but surely America is inching towards metric, largely without anyone domestic or abroad noticing.

Want to make the switch take longer? Continue calling them “idiot units”, a mildly humorous statement from a certain point of view given that it takes more brainpower to use customary units than metric, making the latter far more tailored to idiots. And continue to start flame wars in comments comprising mostly of personal attacks rather than using the many and very legitimate and rational arguments that exist as to why it would be of benefit for the people of the United States to make the switch. In the end, we all know there is no better way to convince someone to do something than making the whole thing a religious war, with you on one side and they on the other…

This article originally appeared on Today I Found Out. Follow @TodayIFoundOut on Twitter.