The preponderance of narcissistic traits and personalities in politics is much less than in show business, for instance. Rather, it is a spectrum.
Most narcissists are opportunistic and ruthless operators.
But not all opportunistic and ruthless operators are narcissists. I am strongly opposed to remote diagnosis. Please do not forget that only a qualified mental health diagnostician can determine whether someone suffers from NPD and this, following lengthy tests and personal interviews. Actually, being feared, or derided is also narcissistic supply. Lasch characterized America as narcissistic.