What is an important theme from The Crucible, and what is the chief approach Miller utilizes to develop that theme? Use examples to support the answer.

The 1953 play The Crucible by Arthur Miller is a retelling of the Salem Witch Trials, an incident that occurred in the late seventeenth century in Massachusetts in which twenty people were executed for practicing witchcraft. The Salem Witch Travels have become synonymous with any incident of extremism, slander, and mass hysteria. These same themes are developed throughout The Crucible, which Miller used as a representation of McCarthyism. McCarthyism was a practice pioneered by Senator Joseph McCarthy in which American citizens were accused of treason without evidence, similar to the accusations of witchcraft during the Salem Witch Trials. 
While Miller explores many themes throughout The Crucible, one that runs through the entire play is that of hysteria. Hysteria occurs when unfounded panic and fear spread rapidly through a population. Miller explores and develops the theme of hysteria by presenting how the fear of witchcraft spread through the people of Salem. When hysteria takes hold, people very quickly turn on their neighbors whom they had previously trusted or admired.
It is an interesting phenomenon, as it works on two levels—people genuinely fear the purported instances of witchcraft, but opportunistic individuals can use the hysterical climate to justify previously unexpressed prejudices and grudges. Reverend Parris uses the townspeople's hysteria to strengthen his social standing, while others like Abigail and Thomas are able to use the fear of witchcraft to take down their rivals or enemies. Essentially, the state of hysteria upends normal social and legal practices and allows people's darker sides to come out under the guise of righteousness and piety.