A Politician's Master?

A recent article by my great friend and political-economics sage Mr. McIver got me thinking about a politician's master:

With government of any kind: no ruler, so far as he is acting as ruler,
will study or enjoin what is for his own interest. All that he says and does
will be said and done with a view to what is good and proper for the subjects
for whom he practices his art. - Plato