Tending the the overall narrative and story, where Agag was once the downfall of Saul (1 Samuel 15:7-35), now Mordecai becomes the downfall of Haman. A reversal of the story.
Mordecai, much like Shadrach, Meschach and Abednego from the book of Daniel, refuse to bow down to anyone other than God. This begins the irrational response of Haman; instead of making an example of Mordecai, he intends to wipe out Mordecai's entire race; the Jews.
As Jews in Exile (scattered away from Judah and Jerusalem because they were overtaken), there is a loss of identity and of power. Haman exploits this and feels threatened by nonconformity.
Immediately our hearts and minds race to Adolf Hitler, a similar threat from years past. For me this is too easy because it allows us to feel like we have overcome this issue of just getting rid of people who are not like us, who have different skin colors or who have differing view points or people who may not bow down to me.
The sinfulness of Haman is repeated in the world around us, see police brutality, death of children shot by those who are supposed to protect them, current racial and class issues that confront american society. The melting pot is exploding.
But the Good news in this story is that God DOES save God's people. The reversal of previous downfalls happens the other way around, good does triumph over evil. It is hard for us to see in the story that is unfolding before us because we, if we are honest, might feel a bit more like Haman than Mordecai.
God helps us in the midst of great conflict in our country, remind us that you will come and save us and remind us that your kingdom will ultimately reign.