Starting from 1953, Roy Cohn was Senator McCarthy's key aide. Before his tenure with the senator, the 26-year old was the US Attorney. Cohn had played a prominent role in the trial that sent Ethel and Julius Rosenberg to the electric chair in 1951. As a Jewish, Cohn could also protect McCarthy from charges of anti-Semitism.

Cohn held an immense amount of power during his appointment in the Senate Subcommittee on Investigations. The young attorney gained a reputation for aggressively questioning individuals who were suspected of carrying out "Un-American" activities.

Roy Cohn was a really close friend to Private First Class G. David Schine. Taking advantage of his position, Cohn tried to pressure the army into giving Schine special privileges. This eventually intensified the clash that McCarthy will eventually have with the army.

Cohn was deeply loyal to McCarthy. In the 1980's, Cohn wrote a book to defend McCarthy and criticized a movie for portraying McCarthy negatively.

Senator Pat McCarran

Taken from http://en.wikipedia.org/wiki/Pat_McCarran

Patrick McCarran was senator to Nevada. As the chairman of the Senate Internal Security Subcommittee, McCarran made many investigations that added credibility to McCarthy's anticommunist persecutions. In the 1950's, the committee he chaired conducted hearings on the Institute of Pacific Relations. McCarran and his associates tried to proved that the Nationalists' defeat in China's civil war was caused by Communist influence in the United States government.

McCarran was also one of the chief sponsers for the McCarran-Woods Act of 1950. This act required all Communist organzations to register with the US Atternoy and members of these organizations were barred from becoming citizens. Americans who remain in Communist associations would lose their citizenship.