I think I know why the US has not adopted the metric system. It’s a strategic thing. Multiplying and dividing by 12 or 16 helps our young folks develop their minds, vs just using multiples of 10 for everything. Generally, the side with the best developed minds, on average, will prevail in a military conflict. That’s a big part of why the axis lost in WW 2. The metric system did them no favors.
That’s very similar to why, in the year 2025, we still can’t get accurate long range weather forecasts. The US has long enjoyed air power superiority over its potential adversaries. Foul weather neutralizes airpower. Accurate, long range weather forecasts would benefit our adversaries.