This isn't "working harder".
This isn't "rebuilding infrastructure".
This isn't "training people in trades".
The numbers are so cartoonishly lopsided as to be a non-starter for categorically replacing Chinese manufacturing.
Establishing regulatory harmony across all those countries is obviously not possible in the same way it is in a single authoritarian state, but if the US made it a priority to create a trade bloc capable of replicating China’s manufacturing capacity, it probably could.
If the US wants to take on China, and actually needs Canada's help to do it -- I can assure you they just set themselves back 10-20 years from achieving that. We no longer have any interest.
The labour forces of Mexico and Canada are not at the US's disposal for these kind of games anymore. For several decades we have been exploited by the US for low wages and cheap resources -- and now there's a regime that's making cheap political points by accusing us of the opposite while trying to emmiserate our populace. So, yeah, no thanks.
Now it's the CPTPP and doesn't include the US.
Canada is looking to the Pacific and EU for trade now (and China as well), so is Mexico.
It's likely that the EU/UK trade bloc will connect with the CPTPP via both the UK and Canada, which connects them to the APAC/ASEAN nations.
Everyone is aware of the power of the Chinese economy and the idea of the CPTPP is precisely to build up a trade economy that can compete and co-operate with China on an equal basis.
In the meantime, China is using its Belt & Road Initiative as a sort of "Marshall Plan" to extend its influence by building infrastructure like ports and rail.
These trade initiatives are at least focused on increasing trade, as opposed to the US "trade policy" which is to use tariffs as a crude form of protectionism and extortion to "bring manufacturing back".
I think you got your timelines crossed - it was Trump who pulled out of TPP (though Clinton also opposed it during the campaign).
It's at the point now where it is self-sustaining, which is why you see China starting to enforce IP Rights, precisely because it is now generating its own IP that it wants to protect.
Any economist would say that if China did just "copy" US technology to make itself more productive, that's good economic practice, from China's perspective.
Moats only worked for a while to protect European castles, they don't exist now.
Ford is openly discussing the idea to have joint ventures with Chinese EV makers, the whole idea is to get Chinese EV techs in exchange for US market access.
TikTok takeover is another good example.
it could be less economical, so Apple has to innovate to be competitive on pricing - with automation, robots, etc.