8. Re-read paragraphs 27-30. How does King respond to
being labeled an "extremist," and how does his use of the
word "extremist" contribute to the tone of the text?

At first King reasons in the letter that he is not of the extremists, he is actually between two extremes in the black community of militant black nationalism and complacency with the status quo. His use of the word extremist adds to the critical tone of the text as he is speaking directly to the clergy who called him extremist and he criticizes all white moderates.

Explanation:

Martin Luther King is turning the tables with his use of the word extremist because it was a label the white moderates applied to him and his followers. First he shows in paragraph 27 that he is not the extremist, that the black Nationalists are the more extreme dissenters who do advocate violence and reject the white population.  In the end King says that even Jesus Christ was an extremist and he was charged and punished for it with the extreme act of crucifixion.  King says also evokes Abraham Lincoln and Thomas Jefferson as extreme in their ideas and says there is actually a need for “creative extremism” to progress towards civil rights and social justice.

The King responded to being labeled an 'extremist' by using various historical figures. He also responded by saying that how there is no correlation to be devoted to a certain specified cause.

His use of the word 'extremist' contributed to the tone of the text by showing the pride of a King, which shows that the King is extremist.

In the initial paragraphs, the King is not said to be extremist because he is actually stuck between two extremes that is the black community of militant black nationalism and complacency with the status quo.

Therefore, it became mandatory for the King to use the word extremist in his tone because he is delivering his words directly to the clergy who are all white moderates.

To know more about the King and his word extremist, refer to the link:

link