I’m not really sure how that’s possible - when I’ve gotten quotes for short run highly automated manufacturing (the stuff the US should be comparatively good at!), the overseas numbers are usually about half those of the US on a per part basis. IIRC can try this for yourself on Xometry by changing the manufacturing location.

But there’s also more than just labor cost. In my experience: when we ask a Chinese manufacturer about something they don’t have the capability to do, they’ll come back with subcontracting options from the factory down the road who can do it. There’s so much manufacturing capability concentrated in a small number of places that every process option is on the table. But in North America, it’s a very different story. Everything is so spread out so your options are dramatically more limited unless you want to be shipping parts across the country.

I’m not saying NA-based manufacturing is bad: the org I work for still does most stuff here for agility, communication, and security reasons. But it’s not cheap.

Opinions are my own.