content: It's obviously going to get to a complicated discussion when you talk about such a long timeframe because this is a decision you have to make again and again and again. Just by the fact that the entire world outside of the US uses metric, it's going to creep in, slowly but surely.       And to be clear, what we're talking about isn't that retail businesses and regular working people start suddenly adopting the metric. But the policy makers keep influencing school curriculum and educational strategy. And I don't think nobody would expect you to stop using Imperial without at least a generation of metrics being taught side by side. This is the language of science, production and global commerce, no american university uses imperial units when teaching physics, chemistry or engineering. Regardless of the political effort, the complex technological standards will pave the way, better education, globalization, and vaning cultural influence of the US, you'll see a lot more of the metrics no matter what.  I ultimately have to point to France when criticizing your public policies, They took up exactly the same stance when threatened with vaning cultural influence. Had no effect.