Is it an alarming fact that "right-wing" implies crazy, but "left-wing 'radical'" is used to mean the same?

What alarms me that media try to influence the votes by constantly using right wing extremist, but never use the term left wing extremist. Or Obama staff constantly harp Right wing extremist and send memo's constantly about them. Those are not right wing extremist on your list. Right wing extremist are nazi's oppose to left wing extremist which are anarchist, communist and such.