We have indeed had other Esthers and Mordecais over the course of our history.
We have also experienced too many Hamans.
This makes the reading of the story of Esther a little difficult, because we have waited so often for the miracle to reoccur.
This said, Purim needs to be interpreted on another level, in terms of the interplay of the forces that go beyond the framework of the story.
The theme of our survival is interwoven throughout the biblical account.
The main characters should be seen as the protagonists of any classical drama but also the models of the key forces that have manifested themselves throughout our history—Good and Evil, the enemies, the friends, and those who remain neutral.
–Rabbi Adin Steinsaltz
From The Seven Lights by Rabbi Adin Steinsaltz