In The Crucible by Arthur Miller, what does the author mean by his statement that "the Salem tragedy developed from a paradox"?

Miller suggests several contradictions that existed and--to some extent--still exist today in American society.  First, the Puritans who make up Salem Village came to the New World to separate themselves from the religious persecution and controversy that they had endured in England, but ironically, during the witch trials, the Puritan and town leaders go after people who disagree with certain elements of the church or minister.  The persecuted become the persecutors.

Secondly, Miller finds it paradoxical that people such as John Proctor who view themselves as impure are the few to speak against the injustice of the "pure" or "religious" court.

Finally, in relation to McCarthyism or modern witch hunts, Miller uses the contradictions of Salem to show that often the fear that fuels many witch hunts is directed at the wrong people. Just as Congress should have been fearful of Senator McCarthy in the 1950s, the people of Salem should have been more fearful of the seemingly "innocent" girls and religious judges and ministers than of those who were accused of wrongdoing.