Act 2 and 3;

The "witch hunts" in the Crucible were an analogy for the McCarthy trials (a witch hunt for Communist agents); both fueled broad mass hysteria and accusations resulting in condemnation.

There are a number of verbal ironies (we've already gone through a number of these earlier), but the most intense moment of sarcasm is probably seen at the conclusion when Hale answers Danforth's inquiry about his visitation of the so called "condemned witches;"

intense sarcasm, when Danforth asks him what he's doing visiting the condemned "witches":

"Why, it is all simple. I come to do the Devil's work. I come to counsel Christians they should belie themselves."