>Quite simply they fear the truth of their attempted coup of a sitting president being proven as fact by an honest Attorney General
They've become so accustomed to corrupt AGs and judges whom they've either blackmailed or bought, that they cannot cope with an honest AG. They can only react as though he is as corrupted as their appointees and assume he's been bought/blackmailed by Trump. My guess is they are so accustomed to corruption that they are incapable of entertaining the concept of a man who upholds truth and impartiality and adherence to the constitution and the law and therefore can only believe that such a person must be under the thumb of an opposing, but equally corrupt, power. Such is the nature of projection.