“The people must believe that they are not being manipulated in order for them to be manipulated effectively.”
However I would like to add that a conscious manipulator as depicted in the image is far less effective than someone who does not even perceive him or herself as being a self serving manipulator in the framework of whatever internal rationalization there might exist.
I would argue that an extraordinary ability for manipulating others paired with self deception in combination with a set of misguided personal believes has cause more suffering in the world than anything else. For those are the false prophets that can rally the masses for war – and for the wrong reasons at that.
Remember – you are not lying when you believe it to be true.