Yup this is what I always tell people – in the US, all science is taught in Metric. (at least in my schooling in the DC area). All physics, chemistry, etc units were in metric. So where it truly makes a difference, it seems to all be metric.

That's why I'm always surprised when I read a story about some scientific endeavor in the US that didn't use metric.

The US uses some metric units for some liquids (e.g. a 2 liter of soda).

For me a big stumbling block is cooking; I like using volume units for cooking, but metric recipes tend to use weight.

Don't you think that weight (or, pedantically, mass) generally makes more sense for many ingredients? 100g of flour is a well-defined quantity, one cup of flour can vary significantly depending on how tightly packed the flour is.

The packing is mostly a function of how you yourself put the flour into the cup/how it was handled and stored before I got to my house. In practice there's not much variation of this sort. And you still want to taste and adjust as needed, so I don't think you would really need to-the-gram precision since there are so many factors like humidity that can impact how much of an ingredient you should use anyways.

Why not use liters?

I think the way it'll happen is by America's loss of manufacturing. That's a big user of units and it's declining. Imported stuff is going to be more and more often metric unless it was also designed in America. So people are going to encounter it more and more. At some point, there might be a price penalty for specifying the less common imperial threads and material thicknesses on Chinese made parts so American designers in competitive industries might start preferring metric.

But it might never go away from daily life. The Chinese still use "jin" as a unit of weight/mass. The communists unified the customary definitions to be exactly 0.5 kg, but even they weren't powerful enough to force everybody to use kg directly. If a communist dictatorship is too weak, there's no hope for a democratic government!