I was thinking that manipulation would become non-effective once someone knows they are being manipulated. So to be most effective, it would have to be un-known

I was thinking that manipulation would become non-effective once someone knows they are being manipulated. So to be most effective, it would have to be un-known. We all know governments manipulate. Generally. But what is the current specific manipulation that is still secret, and thus we are influenced by something without knowing we are being influenced, or even are confident we are not being influenced. or guess, we could be in such a jaded time that people don't believe anything, even if something is true. In such a jaded time, is manipulation easier or harder?