Interpreting Arrow'ss impossibility theorem

Arrow's Impossibility Theorem is commonly understood to invoke a dictatorship that is somehow lurking within our voting arrangements. A well-recognized statement of the theorem is that "any constitution that respects transitivity, independence of irrelevant alternatives and unanimity is a dictatorship". The theorem is really not about dictatorship at all. It is more appropriately interpreted as about the spoiler problem, about the possibility that the presence of a candidate who cannot win the election himself may, nevertheless, violate the "independence of irrelevant alternatives" by switching the outcome of the election between two other candidates. The theorem becomes that no electoral system is guaranteed to avoid the spoiled problem altogether, regardless of the options and regardless of voter preferences.