It doesn’t matter if they stole the “technology”, i.e. how to design RF low observables structures. They have lots of smart people, they would get there eventually anyway.
The real story is that China’s military power comes from the massive trade advantages we GAVE them. THAT would have taken them a century left on their own.
The theory was that trade would moderate their behavior. DID IT?
The problem with stealing technology is that you don’t know how to develop it or use it. And they never test it.
Wasn’t that Kissinger’s idea? 🙄
The real story is that China’s military power is more fake than real.