There was, of course, domestic policy being made in a number of areas during this time. For example, there was a red scare of sorts that helped cause the government to take anti-radical steps such as the Palmer Raids. There was also a wave of nativism, caused in part by fears that immigrants were bringing radical political ideologies to the US. This wave of nativism eventually resulted in the passage of an immigration restriction act in 1924 that was aimed at reducing the numbers of immigrants from certain areas of Europe. The policy was meant to discourage immigration from Eastern and Southern Europe.
The most famous domestic policy of this time, however, was the pro-business policy of the three Republican presidents of this decade. In the previous two decades, there had been a great deal of Progressive reform. This included greater regulation of business. However, Presidents such as Harding and Coolidge were extremely interested in reducing these regulations. They believed in a laissez-faire approach to economic policy. Therefore, the 1920s are best known, in terms of domestic policy, for the pro-business attitude of the Republican Party.