If a low ranking employee in Cincinnati divulged corporate trade secrets, they'd be tried and convicted. If a low ranking employee in Shanghai did the same, what can the US company do? Not much. So it's a low risk activity, that is also actively encouraged and in many cases financed by the Chinese government. This is in no way intended to be disparaging of folks who are of Chinese descent, but rather a reflection of the reality of contemporary Chinese government politics and policies.
Would you get tried in the US for interning at a company and then go to a competitor with all your inside knowledge ? [edit: barring a paid non compete agreement]
Then a step further from that, sure there are laws to prevent you from wholesale lifting corporate data and bringing them out as you leave, but as many laws it will be extremely difficult to detect and prove that happened in many low profile cases. That's why instead of just relying on the law you'll lock usb ports monitor network activity and get laptops returned when someone leaves.
It's kinda like preventing shop lifting, you know it will happen at some scale.
> US company / Chinese gov
How much leverage do you thing a Chinese company has to if a three letter US agency spies on them and pass the info to US companies ? And would you argue that scenario wouldn't happen if a specific Chinese company had a decisive advantage that could severly hurt US interests ?
For the level of copying being discussed, the scenario to compare to is when Google waymo sued Uber for copying files for hundreds of millions of dollars. They were caught copying source files & design docs.
Both for software products and manufacturing products, that's what is going on: exact copies of source code, assembly line configs, etc. Many folks write off selling to China for reasons like this. Initially that means underserving one big market for self-defense. Where it gets next-level painful and crazy is when cloners then take their derived works back to the international market to compete directly with the inventors. By then it has been tweaked, but the core is still the clone.