States was responsible for several terrorist attacks during the 1910s. The Red Scare, a strong backlash to these leftist movements, formed in 1919. The New Deal coalition During the Great Depression, small government conservatism became less popular, and Franklin D. Roosevelt formed the New Deal coalition. The Democratic Party at this time expanded on the reformist beliefs of progressivism, establishing social liberalism and welfare capitalism as the predominant liberal ideology in the United States. Supporters of Roosevelt's liberalism advocated financial reform, increased government regulation, and social welfare programs, encapsulated in the New Deal. Conservative Republicans and southern conservative Democrats formed the conservative coalition during Roosevelt's second term. Following the presidencies of Roosevelt and Truman, however, the Democratic Party moved away from populism in the 1950s. American liberalism also shifted its perspective on poverty during this time, emphasizing it as a long term social issue rather than a crisis that could be fixed with a sufficient response. The Republican Party's progressive wing had dissipated in the build up to the Great Depression. The party instead began to advocate for small business, equal opportunity, and individualism. These ideas became the foundation of modern fiscal conservatism that would define the Republican Party through the 20th century. The foundations of modern social conservatism were also developed by the Republican Party of the 1920s and 1930s, with Herbert Hoover emphasizing politics as a means to protect the American family and American morality. Rather than strengthening of government to do good as advocated by progressivism, conservative Republicans sought to restrict the government to prevent harm. The Republican Party came out strongly against the New Deal programs of the 1930s, arguing that "big government" threatened to become tyrannical. American entry into World War II was debated between isolationists and interventionists from the onset of conflict in the European theatre in 1939 until the attack on Pearl Harbor in 1941. During the war, an ideology of self-sacrifice was promoted and adopted by the American people, including both military service and home front activities such as rationing. After the end of the war, interventionism persisted through programs such as the Marshall Plan. Fascism briefly saw popularity in the 1930s, though it was no longer relevant after World War II. Cold War and the Civil Rights Era The Cold War began in 1947, causing a shift in foreign policy. Americanism developed as its own distinct conservative ideology that rejected foreign