> How do Chinese owned industrial factories in Brazil differ, apart from being more efficient and able to pivot to new markets better? Which seems like useful properties in a war footing?
The factory stops being efficient and easily pivoted the second the people running said factory want it to stop. That, in turn, depends on how friendly you are with the country running said factory.
Let's say there's some sort of negotiations going on between the country that hosts the factory and the country that operates the factory, which, in this case, means a country with a government that has a very deep cadre system that gives them control of almost all enterprises, state-owned or otherwise.
The negotiations (whatever it is, let's just say they're economic for an example) reach an impasse. You are the country that has control over the factory. Sure, the host country has the factory, but they don't have the institutional knowledge, intellectual property, or supply chain deals that your firm does.
Do you ignore this leverage? Hell no. You say "it'd be a real shame if we had to find a new place to make our products for your market", which would imply a serious loss of employment in the region and a massive factory complex sitting empty and decaying.
Unless you're talking about the sort of relationship the US and Japan have, the factory's host country now has to consider that possibility.
> Do you want your war munition manufacturers to say "we'd have better short term bonuses if we didn't manufacture what you need but instead just kept manufacturing our old stuff with no regard for the nations future"?
That's literally how pretty much all industrialized and post-industrialized nations' defense manufacturing sectors work to one extent or another. Some munitions and defense systems are incredibly complex. You can't just move the knowledge about their manufacture over in a few corporate wiki pages; you have to have the greybeards teach the young guys by doing. This happens all the time, particularly with nuclear weapons. If you don't do that, the greybeards retire or die off and no one knows how to make this system that the military has speced, tested, approved, and gone through the bureaucracy of acquisition for. This means they either do without or get to start over from scratch at tremendous cost.