After 1921 and for the remainder of the 1920's America was dominated by a series of Republican Presidents.
Warren Harding - 1921-1923
Promised "A Return to Normalcy" ie. Removal of Wartime restrictions, rejection of Wilson's policies of international involvement, League of Nations and Progressivism (belief that governments should work to improve society).
He believed in Laissez Faire (that Governments should not intervene in business and the economy)
He introduced - a Bill limiting immigration and the Fordney McCumber Tarriff which raised import duties on goods. (Protectionism - imposing tariffs to protect US goods from foreign competition)
His presidency is overshadowed by Corruption amongst members of Government under him. Whether he was involved/aware of/supported these activities is unknown as he died in Office on 2nd August 1923.
Calvin Coolidge - 1923-1929
Was sworn in as President after Harding's sudden death. His campaign slogan was "Keep Cool with Coolidge" Believed in Minimal Government & that the Government's aim and role was to balance the budget, reduce debt, cut taxes, and make hire purchase available.
"The business of America is business" was his slogan suggesting that the freedom of business + economic protection = prosperity for america
1925 - Revenue Act - reduced tax by halving surtax, abolished gift tax and halved estate tax. (this increased consumer spending power and encouraged business investment)
Although seen as Isolationist (wanting to not be involved in other countries), he was willing to engage in Latin America and Mexico if interests were threatened and endorsed America's entry to the International Court of Justice. (though this never happened)
Herbert Hoover - 1929-1932
Voted in under his famous and ironic campaign slogan "a chicken in every pot and a car in every garage". (another slogan was Hoo but Hoover!)
Strong believer in rugged individualism - idea of minimal government in social and economic affairs and places focus on the self reliance and success of an individual through hard work. Takes the responsibility off government to provide welfare. Despite this belief he was a humanitarian and had organised charity work and relief in WW1.
He didn't agree with Laissez Faire, believing that government should work alongside businesses with a voluntary supporting role rather than a controlling one.
After the Crash, Hoover persuaded businesses to continue public work spending - but the crash was too serious. Finally he increased federal intervention & government public works expenditure, provided government loans & set up the Reconstruction Finance Co., However it was "too little too late"