---
title: "Second Red Scare — APUSH Definition & Exam Guide"
description: "The Second Red Scare was the post-WWII fear of communist subversion in the U.S. (late 1940s-1950s), driven by the Cold War. A core Unit 8 cause-effect topic."
canonical: "https://fiveable.me/apush/key-terms/second-red-scare"
type: "key-term"
subject: "AP US History"
unit: "Unit 8"
---

# Second Red Scare — APUSH Definition & Exam Guide

## Definition

The Second Red Scare was the wave of intense anti-communist fear in the United States during the late 1940s and 1950s, fueled by early Cold War tensions, that produced government loyalty investigations, HUAC hearings, and the persecution of suspected communists and sympathizers.

## What It Is

The Second Red Scare is the period (roughly 1947 to the mid-1950s) when Americans became convinced that [communist](/apush/unit-8/context-us-as-global-leader/study-guide/gQBcPKrfySmr9qtQziHd "fv-autolink") spies and sympathizers had infiltrated the government, Hollywood, schools, and [labor unions](/apush/key-terms/labor-unions "fv-autolink"). The fear wasn't invented out of nothing. The Soviet Union really was expanding in Eastern Europe, China fell to communism in 1949, and real espionage cases like Alger Hiss made the threat feel concrete. But the response went far beyond the actual threat, producing loyalty oaths for federal employees, House Un-American Activities Committee (HUAC) hearings, blacklists, and Senator Joseph McCarthy's reckless accusations.

Here's the part the CED really wants you to get (KC-8.1.II.A): both [political parties](/apush/unit-4/expanding-democracy-1800-1848/study-guide/yvZqvo6sEMe2gvvM03AB "fv-autolink") agreed on *containing* communism abroad, but Americans fiercely debated the *methods* used to expose suspected communists at home. The Second Red Scare is essentially the Cold War turned inward. The same fear driving containment policy overseas drove suspicion of neighbors, coworkers, and government officials at home.

## Why It Matters

This term sits at the heart of Topic 8.3 (The Red Scare) in [Unit 8](/apush/unit-8 "fv-autolink"): Cold War and Social Change, 1945-1980. It directly supports learning objective [APUSH](/apush "fv-autolink") 8.3.A, which asks you to explain the causes and effects of the Red Scare after World War II, and it connects to APUSH 8.2.A on continuities and changes in Cold War policy. The Second Red Scare is also a favorite for continuity-and-change thinking across periods, since it echoes the First Red Scare of 1919-1920 from Unit 7. If you can explain why fear of communism resurfaced after WWII and what it did to civil liberties, you've nailed one of Unit 8's central tensions: security versus freedom.

## Connections

### [McCarthyism (Unit 8)](/apush/key-terms/mccarthyism)

[McCarthyism](/apush/key-terms/mccarthyism "fv-autolink") is the most famous expression of the Second Red Scare, not a synonym for it. The Red Scare is the broad climate of fear; McCarthyism is Senator Joseph McCarthy's specific tactic of making sensational, often baseless accusations of communist ties. The scare started before McCarthy and outlasted his 1954 censure.

### [House Un-American Activities Committee (HUAC) (Unit 8)](/apush/key-terms/house-un-american-activities-committee-huac)

[HUAC](/apush/key-terms/huac "fv-autolink") was the congressional machinery of the Second Red Scare. Its hearings on Hollywood and the Alger Hiss case turned abstract fear into public spectacle, and they show how the government itself debated methods for exposing suspected communists, exactly what KC-8.1.II.A describes.

### First Red Scare, 1919-1920 (Unit 7)

Same fear, different fuel. The first scare followed the [Russian Revolution](/apush/key-terms/russian-revolution "fv-autolink") and WWI labor unrest and burned out quickly. The second was tied to a decades-long Cold War with a nuclear-armed Soviet superpower, so it lasted longer and reached deeper into ordinary life. This pairing is gold for continuity-and-change essays.

### Containment and Cold War policy (Unit 8)

The Second Red Scare is the domestic mirror of containment. Abroad, the U.S. used collective security, the Marshall Plan, and the Berlin Airlift to limit Soviet influence (KC-8.1.I). At home, that same anti-communist logic justified loyalty oaths and investigations. Foreign policy and domestic fear fed each other.

## On the AP Exam

On multiple-choice questions, the Second Red Scare usually shows up as a cause-and-effect question (what Cold War developments triggered it, what it did to civil liberties) or as a comparison with the First Red Scare of 1919-1920. Practice questions ask exactly that: why the second scare differed from the first, and what historical trends fed fears of communism. Be ready to point to Cold War context as the key difference. No released FRQ has used the term verbatim, but it's strong evidence for Unit 8 essays on Cold War domestic effects and for continuity-and-change arguments linking Periods 7 and 8. The move the exam rewards is connecting foreign policy fear to domestic consequences, not just defining the term.

## Second Red Scare vs First Red Scare (1919-1920)

Both were waves of anti-communist panic, but the triggers and scale differ. The First Red Scare followed the Russian Revolution and postwar strikes, peaked fast with the Palmer Raids, and faded by 1920. The Second Red Scare grew out of a sustained Cold War rivalry with a nuclear-armed USSR, lasted roughly a decade, involved formal government machinery (HUAC, loyalty programs, McCarthy's Senate hearings), and was reinforced by real espionage cases like Alger Hiss. On the exam, the difference to name is the Cold War context that made the second scare longer and more institutionalized.

## Key Takeaways

- The Second Red Scare was the intense fear of communist subversion inside the United States during the late 1940s and 1950s, driven by early Cold War tensions with the Soviet Union.
- Per KC-8.1.II.A, both parties supported containing communism abroad, but Americans sharply debated the methods used to expose suspected communists at home.
- Key effects included loyalty oaths for government workers, HUAC investigations, Hollywood blacklists, and McCarthyism's wave of accusations.
- Real events like the Alger Hiss case and Soviet expansion made the fear plausible, but the response often trampled civil liberties of people with no actual communist ties.
- Compared with the First Red Scare of 1919-1920, the second was longer and more institutionalized because the Cold War made the communist threat feel permanent.
- For APUSH 8.3.A, be ready to explain both the causes (Cold War rivalry, espionage cases) and the effects (investigations, persecution, debates over civil liberties) of the postwar Red Scare.

## FAQs

### What was the Second Red Scare in APUSH?

It was the period of intense anti-communist fear in the U.S. during the late 1940s and 1950s, when Cold War tensions led to loyalty oaths, HUAC hearings, and persecution of suspected communists and sympathizers. It's covered in Topic 8.3 under learning objective APUSH 8.3.A.

### How is the Second Red Scare different from the First Red Scare?

The First Red Scare (1919-1920) was a short panic triggered by the Russian Revolution and postwar strikes. The Second Red Scare lasted roughly a decade because it was fueled by an ongoing Cold War with a nuclear-armed Soviet Union, and it ran through formal institutions like HUAC and federal loyalty programs.

### Was the Second Red Scare the same thing as McCarthyism?

No. McCarthyism was one piece of the Second Red Scare, specifically Senator Joseph McCarthy's tactic of making sweeping, often unsupported accusations of communist ties. The broader scare began before McCarthy's rise in 1950 and continued after his Senate censure in 1954.

### What caused the Second Red Scare?

Early Cold War shocks did. Soviet expansion in Eastern Europe, the fall of China to communism in 1949, the Soviet atomic bomb, and real espionage cases like Alger Hiss convinced Americans that communist subversion at home was a genuine threat.

### Did both political parties support the Red Scare investigations?

Both parties supported containing communism overseas, but the CED (KC-8.1.II.A) stresses that Americans debated the methods used to expose suspected communists at home. Support for containment was bipartisan; support for tactics like McCarthy's was not.

## Related Study Guides

- [8.3 The Red Scare](/apush/unit-8/red-scare/study-guide/DO0e4A4aiTYvyrkA5oje)

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