We can't stop them, but we can shake our fist at them
As per everything in War, be it with weapons, economy, cyber, espionage etc. If they were able to stop it they wouldn't need to be complaining about it.
Sad fact is that the East is way ahead of the West in cyber warfare, and unlikely to ever let the West catch up.
When China starts setting their policy by the speeches of wannabe presidents I will eat my hat.