Final answer:
McCarthyism was not solely caused by McCarthy, as many individuals contributed to its rise. McCarthy's accusations lacked credible evidence, leading to a decline in his influence and the weight of McCarthyism.
Step-by-step explanation:
McCarthyism was not solely caused by McCarthy but was a result of the efforts of many individuals. By 1953, it was illegal in 39 states to advocate violence due to the collective actions against communism. McCarthy's accusations were not substantiated by credible evidence, and even his strongest supporters advised him to make more subjective accusations. McCarthy's exaggerated or faulty information led to the decline of his influence and the reduction of McCarthyism's weight.