President Harry S. Truman signed Executive Order 9835 creating the Federal Employee Loyalty Program, authorizing loyalty boards and a central review structure to investigate alleged subversive influence in the executive branch—an early cornerstone of the Second Red Scare.
After refusing to answer HUAC questions about Communist Party membership and related issues, the “Hollywood Ten” were cited for contempt of Congress—an episode that accelerated entertainment-industry blacklisting and became a defining cultural front of the Second Red Scare.
Attorney General Tom C. Clark released the Attorney General’s List of Subversive Organizations (AGLOSO), which was used by loyalty boards and other institutions as a guide for identifying groups considered “subversive,” reinforcing blacklist-style screening during the era.
Truman directed that investigative reports and files under the Employee Loyalty Program be kept in strict confidence, citing national security and fairness concerns—highlighting the secrecy that often surrounded loyalty investigations.
Eleven leaders of the Communist Party USA were convicted under the Smith Act (after the Foley Square trial), a major legal milestone that encouraged further federal prosecutions by treating certain forms of revolutionary advocacy as criminal.
Former State Department official Alger Hiss was convicted of perjury in a case tied to accusations of Communist espionage; the highly publicized proceedings fueled public fears of infiltration and became a frequent reference point in Cold War political battles.
Senator Joseph R. McCarthy’s speech in Wheeling, West Virginia, claimed he had a list of Communists in the State Department, helping propel “McCarthyism” into national prominence and intensifying pressure for investigations and loyalty measures.
The Senate authorized and began hearings (the Tydings Committee) to investigate McCarthy’s allegations about disloyalty and “loyalty risks” in the State Department—an early institutional attempt to assess and rebut his claims.
Congress overrode Truman’s veto to enact the Internal Security Act (McCarran Act), requiring registration of Communist organizations and establishing new internal-security mechanisms—one of the era’s most sweeping statutory expansions of anti-communist policy.
A federal jury found Julius and Ethel Rosenberg (and Morton Sobell) guilty of conspiracy to commit espionage, a landmark case often invoked in public arguments about Soviet espionage and internal security during the Second Red Scare.
In Dennis v. United States, the Supreme Court upheld the convictions of Communist Party leaders under the Smith Act, endorsing a broad approach to restricting advocacy seen as posing grave security risks and shaping subsequent enforcement strategies.
President Dwight D. Eisenhower signed Executive Order 10450, revising federal employment screening by broadening “security risk” criteria and shifting responsibility to agency heads—replacing Truman’s earlier loyalty-program framework while continuing intensive vetting.
Julius and Ethel Rosenberg were executed after their espionage conviction, becoming emblematic of the period’s harsh penalties and the high political stakes attached to allegations of Communist spying.
Televised hearings opened as the Senate Permanent Subcommittee on Investigations examined charges and countercharges involving McCarthy, his staff, and the U.S. Army—publicly showcasing McCarthy’s methods and contributing to his political decline.
President Eisenhower signed the Communist Control Act of 1954, a symbolic and punitive measure aimed at the Communist Party USA (and related organizations) during the height of Cold War domestic anticommunism.
The U.S. Senate voted to censure McCarthy for conduct deemed contrary to senatorial traditions, formally curbing his influence and marking a decisive political turning point in the McCarthyism phase of the Second Red Scare.
In Watkins v. United States, the Supreme Court reversed a contempt conviction arising from HUAC testimony, emphasizing due process and the need for clarity about a committee’s investigative scope—an important judicial constraint near the end of the 1947–1957 period.
McCarthyism and the Second Red Scare (1947–1957)
