The setting in The Crucible was one that was in Salem, Massachusetts
McCarthyism
used the backdrop of the Salem Witch Trials
was one of the darkest periods in time ever

used the backdrop of the Salem Witch Trials

Explanation:

The Crucible is set against the backdrop of the Salem Witch Trials. Although the story unfolds in Salem, Massachusetts, it occurs during the 17th century, not in the time the play was written. McCarthyism would be the backdrop amidst which The Crucible was written. Arthur Miller was one of many victims of the persecution of suspected members of the Communist Party during the 1950s, and his play being set during the witch trials of Salem was his way of denouncing the political persecution America was subjected to at that moment.

c

explanation:

the speech this question is referring to is president kennedy's special message to the congress on urgent national needs, may 25, 1961

kennedy responds in a very direct and concrete way to those thinking that communism is a positive system:

"yet their aggression is more often concealed than open. they have fired no missiles; and their troops are seldom seen. they send arms, agitators, aid, technicians and propaganda to every troubled area. but where fighting is required, it is usually done by others--by guerrillas striking at night, by assassins striking alone--assassins who have taken the lives of four thousand civil officers in the last twelve months in vietnam alone--by subversives and saboteurs and insurrectionists, who in some cases control whole areas inside of independent nations." (kennedy)

president kennedy presents communism as cowardly, as a hidden and treacherous weapon that strikes from the shadows like thieves, he represents the system as not even being capable of showing and open and overt attack or confrontation. to finish up the response, he expresses that the system attacks even a country's idependence and freedom.