They'd more likely split themselves laughing.
The solution to threats to global economic integration is to address the threats to global economic integration. It's not to cannibalise our own full-employment high value economies, by diverting enormous capital and labour into duplicating vast swathes of lower value jobs we don't actually have the work force for anyway, just so we can pay unaffordable prices for the resulting goods.
We probably both agree it's an absurd fantasy, and the people trying to make stuff like this happen are implementing policies that ensure that it won't, such as putting tariffs on the inputs they need to build out this domestic manufacturing capacity in the first place.
> The solution to threats to global economic integration is to address the threats to global economic integration.
So permanent world peace. That sounds much easier.
Amd it isn't only geopolitical threats we have to worry about. The world's hard disk supply disappeared with a tsunami in Thailand. Taiwan is vulnerable to those and earthquakes. Efficiency and robustness are at odds and we are leaning too far towards efficiency. Even if China hadn't been so large it could absorb the costs of capturing the world's entire manufacturing base with subsidies, centralizing that much has risks completely apart from politics.
Thailand was flooding, not tsunamis.
It’s one thing when toys, pots, furniture etc. is made somewhere else. It’s a completely different thing when your high tech is manufactured there.