No asymmetry, we only hear about it when successful. One thing to also keep in mind is that intelligence organizations like the CIA typically work through intermediaries such that a cybercrime organization in South Korea may not know they’re executing an attack on China on behalf of the CIA — they may have already wanted to do so for their own reasons and the CIA just made sure they found the right info to execute it.

The Chinese media would label such an attack as a US hack on China, while the US media would report it as a Korean hack on China (meaning you probably never hear about it at all unless you’re in the business).