I feel that it's reasonable to expect that Russian, Chinese, and EU members are tracking American activities worldwide. It would be a failure of their various institutions to not track and influence nations and institutions with world-relevant power or influence. This includes both monitoring and more aggressive attacks.

I also feel that as an individual person, I have no defense against this, partly because it's generally easier to attack a system than to defend it, partly because of the asymmetry of costs in defense vs attack leading to the lack of business or personal justification for effective defense spending, and partly because electronic monitoring and attacks are difficult to investigate by their international nature.

So if American institutions discovered some attack, they would release the information with proper political timing to influence national narrative, thereby inflating their agency importance, or it may further some group goals, the news media may proliferate and bark about it, and no national administration, including the American one, would be surprised at all. It would not update anyone's view of the world in any way.