The biggest problem is that the base underlying our manufacturing capability has almost completely evaporated. You need tool and die companies to build parts for your manufacturing machines, but almost none are left. There are only a few plastic injection manufacturing companies left, and they are either fully booked or on the path to shutting down. (No, you can't 3D print products for the mass market, it's way too slow and expensive.) Young people think of trades and manufacturing jobs as fall-backs that only drop-outs who couldn't hack college get into. You will make many times more money as a salescritter convincing people to buy things they don't need than using decades of engineering experience to build the things they do.
It's a popular misconception that China's manufacturing advantage is cheaper labor. This was _maybe_ true for a while, their advantage right now is that they have all the things mentioned above: they have the tool and die shops, they have the supply chains, and they have workforce. They can go from product idea to shipping in a week. I do not celebrate the Chinese government for much, but making sure they had a robust manufacturing base from top to bottom was the biggest and most important thing they have ever done. The US government let ours wither and die. Which has made our economy remarkably fragile and essentially decimated the whole idea of a blue-collar middle class.
Destin from Smarter Every Day encountered all of this when he tried to make a better grill brush using only a handful of parts and _still_ did not manage to make the whole thing using only US-originated parts. It's a fascinating window into how hard it is to make anything at all here: https://www.youtube.com/watch?v=3ZTGwcHQfLY