Where metric units are important, e.g. science and engineering, they are already used.
2. it's got the advantage that you're using the same measurements as all your trade partners so people don't need two production lines anymore
3. it's got the advantage that people going into science and engineering don't need to build a whole new set of unit references because they've got the one which already works
4. the "huge expense" is pretty much made out of whole cloth for the purpose of saying you can't switch, the UK's metrication cost basically nothing except for road sign replacements which is why those are still imperial
We already do that.
> 2. it's got the advantage that you're using the same measurements as all your trade partners so people don't need two production lines anymore
Two production lines? For what?
> 3. it's got the advantage that people going into science and engineering don't need to build a whole new set of unit references because they've got the one which already works
Yup, failure to use the metric system in everyday life is why the US has the worst scientists and produces the least scientific output. Oh, wait.
> 4. the "huge expense" is pretty much made out of whole cloth for the purpose of saying you can't switch, the UK's metrication cost basically nothing except for road sign replacements which is why those are still imperial
I agree with this one. It probably wouldn't be terribly expensive to implement, though I would question the priorities of anyone who is really hung up about it (like the grandparent post who started this whole discussion).
Failure to use the metric system everywhere cost NASA a $125 million Mars orbiter just 16 years ago, and yet here you are, insisting that this is not a problem, and throwing in a non sequitur to justify the position.
No, bureaucratic failure to address the concerns of people who spotted the error well in advance of the launch cost NASA $125M. The investigation report makes that clear, especially when it goes on to make recommendations for avoiding future mishap; nobody recommended that the engineers needed to brush up on their units.
And yet here you are, insisting that the issue was that we didn't switch over to the metric system, and throwing in some unsupported claims to justify the position.
Do you really? Whenever I hear an American telling the temperature of the weather, I have no idea what they mean. I have to guess from the context if it's hot or cold, and even what units they're using because they rarely mention the "Fahrenheit" part.
Conversely, how many Americans would recognize that "35 degrees" is blisteringly hot while "15 degrees" means you'll need a jacket and "40 degrees" could kill you if you don't find shelter quickly?
Use SI and ISO standards for everything.
ISO A4 paper, ISO time (2015-08-14 23:52 UTC+2), Metric, etc