It's Time For The US To Go Metric

The US has a love affair with imperial units: height in inches, milk in quarts, weight in pounds. You name it and it's measured in imperial. The only problem? Imperial is dumb. The US should cast off those shackles and join the rest of the world by embracing units that make sense. It should go metric, once and for all.

The US is one of the few countries left in the world yet to convert to metric, and this petition is lobbying the nation's lawmakers to change that. It was created on December 31 and is yet to gain much traction. Why make the move? A (metric) ton of reasons.

Imperial is archaic and irrelevant

Let's take a step back. Imperial measurements have roots which can be traced back — sketchily — though Egyptian and Persian history, though the first occurrence of a measure we all know can be found written out in the Magna Carta, signed in 1215, that reads:

"There shall be one measure of wine throughout our whole realm, and one measure of ale and one measure of corn — namely, the London quart; — and one width of dyed and russet and hauberk cloths — namely, two ells below the selvage…."

Priorities. Anyway, the imperial units we now know slowly evolved over next 600 years, being added to as and when required. Eventually, they were gathered together and made official in the United Kingdom in 1824 by a Weights and Measures Act. US weights and measures are — very subtly — different to those in the UK, and were made official in the Mendenhall Order of 1893. It was updated in 1959, sure, but its roots are in a bygone age and, as a result, they now make little sense.

There are too many imperial units

The imperial measurement system employs completely different units for each measurement — and each one can be measured using one of many different units. If that doesn't make much sense, let's try a small comparison. Take, for instance, units of volume. In imperial, you can take your pick from:

gallon, liquid quart, dry quart, liquid pint, dry pint, fluid ounce, teaspoon, tablespoon, minim, fluid dram, gill, peck, bushel, cubic inch, cubic foot, cubic yard, cubic fathom, cubic rod, cubic furlong, cubic mile, cubic league, cubic mil, cubic pole, cubic perch, cubic hand, cubic link, cubic chain

In metric, that list is a little shorter:

litre

OK, so you have to include a prefix to shift by factors of 10 — centi means a hundredth, milli means a thousandth, kilo means a thousand, and so on — but you only need to understand one fundamental measure. The rest is about scaling.

It's impossible to scale imperial easily

And that scaling is hugely important. Think about how you shift between length scales in your head: in imperial, there's no consistency. You have 12 inches in a foot, three feet in a yard, 1760 yards in a mile. There is no neat way to jump between those units without tortuous mental arithmetic.

Conversely, metric units rely entirely on factors of 10 — perhaps the easiest mental arithmetic possible. The best bit, of course, is that metric prefixes apply to each and every metric measurement: move to volume, or weight, or whatever, and they work just the same. You only have to learn one rule, and from then on things are easy.

And that's the wonderful, beautiful thing about metric: it's beguilingly simple and as a result extremely powerful. The fact that the US — perhaps the world's leading technological and scientific power — chooses to make life more difficult for itself by using an archaic set of measures is mind-boggling. The fact that at times the refusal to change creates a measurement barrier, which makes collaborative work between countries almost impossible is a joke. It's time to change that. It's time for the US to leave inches and yards behind, and embrace a glorious metered future.

Picture: Håvar og Solveig/Flickr

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They actually tried already, there is some highway signs in Kentucky that are in KM's. It'll never happen, I've tried to explain how metric works to a few Americans (it's true, they really don't understand it). You'll find many engineering companies over there do work in metric, it's just the average Joe that is stuck in imperial world.
However, they aren't alone are they? Doesn't the UK still measure distance and speed in Miles and MPH?

a lot, if not most US engineering is still in imperial.

My favourite imperial unit is the acre-foot, which is used for water volume in rivers for engineering and geology.

OMG That must be so hard for tasks like calculating the mass of a body of water.

How many arms or elbows is that exactly ?

How many biblical Ark cubits is in an elbow anyways ?

Maybe they could revamp their out of date poxy constitution as well so classrooms full of 7 years olds don't get shot to death by madmen ?

Sort of. They officially moved to the metric system, but most measures are still imperial dual labeled with their metric equivalent, and road signs are miles. Apparently Brits are not smart enough to manage driving at safe speeds if numbers on signs change.

The supermarkets are metric, but lots of corner shops and markets still speak pounds.

Hah!.. Good luck with that.!

If the government really wanted to switch, they could get everyone on board pretty easily.

Just pay the NFL, MLB, NCAA et al to use metric. The changeover would be done quick smart once Joe Average has a reason to use it.

I think that you are right about that. The only thing holding it back is that a yard is smaller than a meter. So they would either have to start marking their fields in 9.144 meter blocks or make the fields longer and run the fields in 10 meter blocks.

Last edited 04/01/13 9:58 am

A meter is bigger than a yard...

1 yard = 3 feet.
1 meter = 3.28 feet.

In fact you even went on to google to find out that 10 yards = 9.144 meters but still didn't put together that a meter must therefore be longer than a yard.

Epic failure dude. Go to the back of the class!

Ok guy's I had a slight mental laps. There's no need to be dicks about it. It also doesn't invalidate the point that I was trying to make.

@Daffy I don't really see what's so epic about what I wrote. It was neither poetic or heroic. Although I guess if I was trying to make it either of those then it would be an epic failure as it achieved neither. Thanks for the feed back though, it really helped enlighten me.

http://lmgtfy.com/?q=define+epic
http://www.urbandictionary.com/define.php?term=epic

Oh and by the way it's now been fixed.

Last edited 04/01/13 9:59 am

you care too much.

http://i.imgur.com/eR18M.jpg

Says it all, really.

^ awesome.

+1 :)

While we are at it we can get them to convert to Celsius instead of Fahrenheit for temperature. How does it make any sense that the freezing point of water is -32 degrees? Having it as zero makes a lot more sense, because you know just by looking at whether there's a negative sign on the number or not whether it's below freezing or not.

@whitepointer I think you'll find that water freezes at.+32F, not -32F (And boils at 212F)
Still doesn't make it any more sensible, though.

Oh yeah. Makes it even more stupid.

Going metric would include that, as Celsius is metric while Fahrenheit is imperial.

Technically speaking the SI system uses Kelvin rather than degrees Celsius.

Kelvin RULES!

ABSOLUTE ZEROOOOOOOO!

Kelvin and Celsius have the same magnitude though, which makes for easier mental arithmetic. Take a temp in C and subtract 273.15 to get K. Much easier than trying to convert F to C or vice-versa.

Yeah, because basing the temperature scale on the freezing and boiling points of water makes heaps of sense.

Makes more sense than how the Fahrenheit scale was determined.

basing it on water is probably better than basing it on salty water ie. fahrenheit

How about writing an article about people in australia that insist on using imperial for height. I always say my height in cm but people always ask how much is that in feet and tell them im 195cm = 6.3976377952695005 feet , People of australia please stop using imperial even if its just for height as i cant remmember long numbers..

Don't know what part of Australia you reside in but I've never been asked for my height in an imperial format.

Really? You don't hear people talking about how they're 6 feet tall or 5.6 etc? I guess I'm comfortable with either format really, but even though I was born in the era of metric, I still learned about people's height in imperial first.

Yeah - it's weird. I'm from Australia and when talking height people always talk in feet and inches "yeah mate, just over 6 foot ey". Occasionally I hear older people talking about weight in imperial "Ol' Dorris lost 2 Stone in a month". Everything else is metric.

I have - it's generally the older generation who can't visualise centimetres...

lol no, it comes from alot of guys really, alot of whom used to watch NBA and would compare theirt height to the guys playing. 6' has alwasy been the abitary measure of "i'm tall". More people relate to heights in feet and inches, but that is just part of the Americanisation of Australia.

I would never refer to any other length in feet and inches, unles si am talking to someone from US.

It's mainly because most american programs they show on tv use it.
Also it's a smaller number for people to remember and guess with - I don't think it will disappear for a long while. At least not until our TV shows start to use it a lot more commonly and the US use it a lot less.

It's not because of US TV shows. It's because Australia also used the British imperial systems until relatively recently, beginning the conversion around 1966 and ending around 1982.
Having grown up, in Australia, with adults that were familiar with imperial measurements, I have no difficulty in relating imperial length measurements to metric and vice versa. The industry I work in also facilitates maintaining this knowledge.
Anywhere that US designed equipment is used, eg. locomotive, automotive, heavy transport, marine, you will find someone who knows an inch is 25.4mm. Once you know there are 12 of those to a foot and three of those to a yard, you're on your way.
Anyone looking to understand civil engineering projects in Australia completed before this time will also be familiar with imperial measurements, not just for distance, but weight and volume. Until those bridges and buildings and tunnels are demolished, someone will need to know at least where to find the information to convert the units used.
I'll admit that there are some Australians...Victorians mostly, who get their life experience and influence from watching too much US TV but it's short sighted and ill informed to suggest that it's the reason we haven't fully let go of the imperial system.
One thing I don't understand though, and don't know if it's still true, why marijuana was sold in ounce and pounds when I was a teenager??

Yep. My mum measures a persons height in feet and weight in stone.

I have three occasions where imperial works: my height, the size of my member and how big a baby is. Other than that metric all the way.

No offense.. But people who give me their height - in the rare cases i actually need it - in CM annoy the HELL out of me. Telling me you're 180cm doesn't really help me picture it. I don't need it in feet, but at least tell me in METERS.. please. Telling me you're "1.8 meters" gives me more to work with than "182cm" it would be like american's given their height in inches, which might happen, i dunno.

But generally, at least for me, it makes a lot more sense to give length, height, weight in the largest measurement possible. Its going shopping and buying meat by the gram when you could do it in kilograms. I don't want it in CM when i can have meters instead.

But thats just personal preference i guess.

Do you seriously have trouble converting 182 cm to 1.82 meters in your head? what difference does it make when its so easy to convert - exactly the point of this article. If you really want to do it the 'American' way wouldn't you need people to tell you they are 1 m and 82 cm tall. Americans would say 6 foot 1 inches not 6.083333 Feet.

The only people who would do this are likely to be over 80 years old and they retired before the mid 1980s.

I am 51 years old and I cannot remember any of the old Imperial measurement system I only know SI measurements.

The US is officially metric already. It's just not recognised by, well, anyone.

you would pretty much have to drag them kicking and screaming to make it happen,

I still remember the one thing that stood out to me on my first visit to the US. The fuel price signs outside gas stations still showed fractions eg 199 9/10 per gallon instead of the much simpler 199.9. America really is quite backward.

Except that cents are after the decimal. It would be 1.999, which would probably be more confusing since its really a rarity to use fractions of cent

Where have you seen a petrol station use \$\$\$ for their fuel prices? Its always in cents, not 1.549 per litre, its always 154.9 per litre. I used that price as an example as that is the unleaded price at the moment where I am.

In the US, which was the topic of the article. It is always \$1.54 9/10. and it is per gallon not per liter

See, that is the beauty of Metric, you can either stick in the decimal point (call it Dollars) or leave it out and call it cents, it is still intelligible, if you do that with any imperial measurement, you get.... shit, and you can't smoke shit.

But you don't get shit, you just get fractions of that unit. People are fine with a half of a gallon even though it could also be 2 quarts. You aren't required to use the smallest whole unit when working in imperial units.

If Imperial is Irrelevant, why are you trying to get people to stop using it? I'll tell you why, because the UNITED STATES uses it, and THAT makes it relevant. Saying that something is irrelevant when the most important country in the world is using it, is DUMB.

The United States started trying to convert decades ago. We didn't like metric, so here we stayed.

And as for things like "doing mental math." So what? It's harder, but NOT HARD. We teach first graders to convert inches to feet to yards, so it can't be THAT tough.

Sorry, whoever you are......not happening any time soon.

And to the arrogant idiot above who thinks you can't EXPLAIN metric to Americans, good grief dude, it's not like metric is difficult. We teach it in school, most Americans can function just fine in metric if we HAVE TO. We just don't HAVE to.

Personally, I like inches and pounds and gallons, they have PERSONALITY. Nothing in the metric system has personality.

hahaha this made my day :D

...and thats what we're fighting against. "PERSONALITY" and the US God complex.

I think I lost a few brain cells reading your argument of "America = Awesome, America uses Imperial, therefore Imperial = Awesome too!"

Get off our site. This is for Australians.

LOL personality. Tell that to the crashed Mars probe.

You seem to be oblivious to the fact that America is the only country in the world that thinks America is the most important country in the world.

That's because America thinks the world consists only of America, Afghanistan and Iraq. Occasionally Israel too.

Case in point: "The world series" I laugh every time..

"Saying that something is irrelevant when the most ignorant country in the world is using it, is logical."

*fixed*

lol! most important country in the world?

America the Brave can't work out more guns = more dead 6 yr olds dead

It'll take a while to work out the decimal system.... Dividing by ten is a bit too logical

One thing i agree with you on, Imperial measurements sound a lot better, when saying things are far away we even say "that's miles away" not "thats kilometers away", "the whole 9 yards" not "the whole 8.23 meters" etc.

I can understand America's reluctance to change, as i refuse to adopt the stupid kibi/mibi for binary (because it sounds stupid). On the other hand i have no idea why they stayed with Imperial once metric was conceived (3 years after independence day) since they hated the brittish (enough to drive on the other side of the road), well i presume they hated with brittish more than the french.

Actually they used to love the French, seeing as the French basically won their War of Independence for them. They didn't change until WWII

Did you really just say that the US is the most important country in the world? Are American's that egocentric?

Evidently units of measurement have more personality than you'll ever have.

"most important country in the world"?

that, friend, is a very big call that i would love to see solid supporting evidence for....

This guy, man. this guy. Either a troll or an idiot, probably the latter. Also, Americans might think they are the most important country, but they aren't.

Yeah, everyone knows Eritrea is really the most important country.

Saying that something is irrelevant when the most important country in the world is using it, is DUMB.
- Some of the most important measurements in your country are done in metric. The rationale that justified the use of the system is no longer relevant.

The United States started trying to convert decades ago. We didn't like metric, so here we stayed.
- TRANSLATION - "The government made a half-assed attempt to change to a system experts correctly recognised as more logical and superior in every way, and the people were too dumb to accept it"

And as for things like "doing mental math." So what? It's harder, but NOT HARD. We teach first graders to convert inches to feet to yards, so it can't be THAT tough.
- I can convert from a whole number of millimetres (.03 of an inch) to Kilometres (.6 miles) in a single operation i can perform in a fraction of a second, just by moving a decimal point. To make an equivalent conversion in imperial, you would have to do several operations - more operations = more room for error. Additionally it simply makes more sense to have measurements that go up by factors of 10 rather than arbitrary numbers.

And to the arrogant idiot above who thinks you can't EXPLAIN metric to Americans, good grief dude, it's not like metric is difficult. We teach it in school, most Americans can function just fine in metric if we HAVE TO.
- In other words they won't learn to use a superior system unless they're forced to.. Presumably because they're too lazy or they don't like learning or they don't care.

Personally, I like inches and pounds and gallons, they have PERSONALITY. Nothing in the metric system has personality.
- You know what else had personality - the geocentric model of the universe. The point was that it was wrong and illogical and useless at what it was meant to do. Like scientific models, measurement systems are designed to (surprise!) measure things! In most professional context this also necessitates conversion between units. Something that is vastly more logical and simple with the metric system. Scientists, industrial designers, engineers and countless other professionals that measure things often, use the measurement system to measure - not to keep them company, to have conversations with ("oh that gallon, he's such a kidder, what great personality!").

You, sir, are hilarious. Thankyou.

The reason America still uses Imperial is because of people like you!
"Imperial measurements sound better, they have personality.. blah blah, we will never change!" what a load of spunk! The article isn't denying that it will be a hard change for the people of America, you know getting over its adorable personality will be hard, with all those cute fractions and bubbly sounding words, but it is laying out the facts as to why America need to pull thier finger out, tuck thier head between thier legs and just go metric.

Don't worry when all the Americans are working as gardeners for the Chinese they'll learn Metric fast enough.

The catch with the harder not hard argument is that it still slows you down. With day to day baking a cake or how far to your parents house measurements that's fine. However when you get to serious real world math imperial measurement puts you at a massive disadvantage. It's a legitimate handicap.
Think of it this way, you wouldn't count on your fingers and toes. You wouldn't run with your shoelaces untied. You wouldn't use a knife instead of a saw or a shifter instead of a hammer. All that stuff is harder not hard but you can't operate that way and expect to come out anywhere near the top.

The rest of the world has caught up to American standards and even started exceeding them. If you guys want to stay relevant outside of the entertainment industry you've got to work harder AND smarter, and metric measurement is one of the first steps towards doing that. Ten or twenty years from now you're not going to be able to keep up with the rest of the world intellectually if you stick with such a backwards system.

Everything in Australia should be measured in metric international measurements. The Americans are soon going to be the number two economy in the world with China as number one and they will have no alternative but to change over to SI, they have already realised this.

Can't use kilometres in country music. No dice.

Also, consider that song called I'm Gonna Be by the Proclaimers:

"And I would walk 805 kilometres, and I would walk 805 more, just to be that man who walked 1610 kilometres to fall down at your door."

Last edited 03/01/13 12:04 pm

ever heard of 'Ks'?

For goodness sake, the US military already uses metric and they reduce everything to one syllable as soon as possible (klicks).

The Proclaimers are from a country that uses the metric system.

Scotland still uses miles, though. As does the rest of the UK.

Last edited 03/01/13 4:14 pm

Damn you, you entirely correct person!!

We're in the computer age. We should be using more base-2 (or perhaps base-8 so we can use our fingers) rather than base-10 systems since they are far easier to convert into "calculative" information. We even already have the prefixes: Kibi, Mebi, Gibi, etc. (each is 2^10 greater than the last) that roughly correspond to our current metric prefixes.

VIVA LA REVOLUTION!!

The main reason America hasn't taken on the metric system is that they can't handle the correct spelling of litre and metre...

...Oh, and that they'd have to abolish the micro scale, as its prefix is practically a 'u', and they've been getting rid of those since the 1800s

All drug smugglers use kilograms, or "keys". So the USA is slowly being pushed into the metric system.
When it comes to Imperial, why favorite is: how much is an ounce? First you have to say, fluid or solid? Then: US, British - or Troy?
Multiple possible answers, when converted to metric. The metric versions don't change.

The US, Liberia, and Myanmar are all together on this Imperial thing...

http://www.joeydevilla.com/2008/08/13/countries-that-dont-use-the-metric-system/

I am an American that moved here to Australia two years ago and I have to say that this article made me smile. My wife and I have a spirited discussion about this on a regular basis. I understand the metric system quite well and operate in it for scientific measurement (mL's, grams etc), but when it comes to anything larger than say 20 cm or a Kilo I switch to Imperial. Don't ask me why, it makes no sense. If somebody says a room is 3674 mm wide I have no basis for visualization. If you tell me that it is just over 12 feet I immediately know how large a space you are talking about.

Intellectually I "get" metric, but I operate in feet, yards, and miles. I can understand the metric equiv, but I don't like them. Don't get me started on Kilowatts vs Horsepower....

I would say that the author of the article was just trying to stir the pot.

The US is as likely to give up feet, yards and inches as Aussies are going to give up grog.

The biggest barrier to adoption is probably american football, 91.44 meters in field length is just an ugly number. Notice that I spelled Meters properly, not with some ridiculous francophone spelling. Why on earth would you put the r before the e?

The 'r' goes before the 'e' because that is how you spell the word. You spell metre meter when you are spelling the word like a semi-literate religious outcast banished to the colonies.

Just so you know, Australia is a more recent British "colony" than America..

Sorry to burst your bubble but Australia is still technically a colony as we never declared independence. Her Majesty if still our Head of State.

Maybe study how the commonwealth actually works. Queen is head of state of separate independent nations as ratified in their respective constitutions. Learn a bit of international law

Well..people used to SI units usually just visualise the room as just slightly shorter than 4 metres wide.

No idiot would think of visualising a long distance in mm.

I don't see you visualising that 12+ ft distance in inches.

mm are used all the time in construction. (i.e. room size)

Yup, millimetres might be used on the blue prints, but just shift the decimal point 3 spaces back and you've got your number in metres. How difficult is that?

As Lachlan said, construction is done in mm. It makes far more sense to have one unit to describe all measurements ( you rarely talk about sub-millimetre units in construction- carpenters aren't that accurate!;-)

On the other hand, all my trout are in pounds!

While I much prefer metric, being an Aussie, at least the yanks are consistent and use imperial for pretty much everything. I have to use a really screwed up set of standard measurements, being a glider pilot in Australia. We measure altitude in feet, except when going for certificates or records when we need to have a certain height gain in metres. We measure airspeed and vertical movement in knots. We measure distance and speed over ground in kilometres and km/h. We measure runway length in metres. And we measure air pressure - important, to calibrate altitude - in hPa or mbar (same thing really.) It's a pain in the proverbial when trying to figure out how many ft altitude at nominated air pressure you need to reach a target, given X km distance, Y kts airspeed and Z kts sink rate... All aviation calculations would be so much easier if it was metric across the board

The other benefit to Metric which is not mentioned is that the three units are inter-related (1 kilogram is the mass of 1 litre of water, 1 litre is 1000 cubic centimetres) which can be extremely powerful as well.

There are major issues with the change, its not just as simple as switching to metric. In many cases it would be easier, however, the error in conversion is difficult. By changing lad plots to metric, because of the difference in rounding by the time you got to the Mississippi you would be living in your neighbors house. I remember that in the cold war the Russians got a downed american plane, but had trouble reverse engineering it because of the differences between metric and imperial units. In the end they trained their engineers to use imperial units in order to reproduce it.

Not really correct in the modern era. The official measure of one inch is exactly 25.4mm. Length and area are already perfectly linked to the metric system.

Wow, i was totally unaware of the change.

You will find that the USA use Metric for all of the important things these days (land surveying, mars landers (after the earlier disaster) etc). They realise that their people are a little slow on adopting new measurements, so they give them Ipads measured in inches, while the chip technology is all at 25nm.

(It goes back a bit before yesterday.... (Wikipedia: "The vast majority of U.S. customary units have been defined in terms of the meter and the kilogram since the Mendenhall Order of 1893 (and, in practice, for many years before that date)." )

The UK is the same they have surveyed the country since 1972 in metric, but translate it into inches and yards for the metric illiterate (though they spend 12 years at school teaching them metric, they still don't really get-it.). (Motorway exit markers in the UK are measured in Metres, but the punters think of them as 300 yards etc... but now they buy their petrol and milk by the litre... )

In Australia, we are versatile, there is no problem rounding in imperial because it has Huge units which are great for imprecise measurements, while the metric is better for easily determining precision. In Engineering, when using imperial they (Everyone) actually metricise it all and talk in Thousanths of an inch (that is 3 numbers after the Decimal point), So to say you are 6 foot 2 inches general is ok, but for your Licence they may record it as 1.880m (sorry if the rounding is a bit wrong).

Time for the US to realise that 300 million people using a unique form of Imperial (not really imperial, but US Imperial) are not that important in the scheme of things, 1.3 billion Chinese and 1.2 billion Indians will show that metric as an official international standard has already won the war....

In the end, I am happy converting, 0.30 cal = 7.62 mm, 30 grains = 1.944 g (kg/1000) of powder, stick in a 180 grain bullet (11.66 grams) = one fast bullet (foot per second and km/hr are similar.

(1 foot/sec = 1.097 km/hr) see it is easy in the end but to convert to energy you need to worry about something called a slug (slg/ft/sec = 32.174 lb/ft/sec), which is a bit weird.

We all love to hate the American way of doing things, it wouldn't be Aussie any other way...They still think that they won us the war and we owe them everything... so what did China do for us? (they sure are getting everything.)

When I was working as a builders labourer we measured all timber out in feet and millimeters. This is because all lengths of timber are 1.8m and 2.4m, or 6 foot and 8 foot, so when calling out measurements you would measure to the nearest foot and then how many milimeters to the edge or the cut marker. We did this because 1) it was faster to call out say "Cut at 6 foot, 184" than it was to call out "Cut at 1m 98.4cm" and 2) I was the only guy on the site under 50.

The kicker for me is the fact that they went to the effort of changing the spelling of most of the metric units, but never adopted it. Meter = Metre. What's up with that?

Ah, the United States of America. The country founded by people escaping Imperialism, who ended up becoming even more imperial themselves.

The US will have a black president long before it goes metric. Just mark my words, a real, black president one day.

The strangest one is liquid ounces. Say a bottle of Hennessy 40oz (rappers drink them) is weighed, and not measured by volume like I think liquids should be.

Some imperial measurements help me visualise more, I agree with the poster above. As in a know how tall 6" is.

While we are at it, can we ask them to stop putting "Z" in everything? ;)

Americans will go metric about the same time they stop thinking guns are an inalienable right.

Fact is, people that matter in terms of progress and academics use Metric, even Americans and British.

Let general populace use whatever works. Expecting them to change hundreds of years of habit is like asking them to stop using colloquial slang. Even in Australia most of the older generation use feet to describe short hand length (though not yards or miles unless really old and likely ex-pat Brit). I will still use feet to describe a persons height in general conversation it's a sneaky way to be inexact. It's harder to say, "About 178cm".

I'm surprised that nobody has raised that most American of considerations yet - CASH! This will never happen until a sufficiently connected politician buys out a company that makes the road signs and/or any of the other signs that would need to be changed to make this work in the real world. When that day comes, then metric won't be far behind. The cost of doing this is playing a large part in the resistance.

I deal with a lot of US based engineering firms and have traveled there pretty widely. Many of them get metric and are happy to converse in it because they use it regularly dealing with the rest of the world - they're not all nearly as egocentric as Dave "the Muppet" Melges above.