Americanism, also referred to as American patriotism, is a set of national values which aim to create a shared American identity for the United States that can be defined as "an articulation of the nation's rightful place in the world, a set of traditions, a political language, and a cultural style imbued with political meaning". The concept is "famously contested" and there is no consensus on "which is the true or authentic... exposition of Americanism... because each of these texts ... is informed by different interpretations of the nature, purpose, and goals of Americanism."

Americanism is not merely nationalism and can cover two different meanings: the defining characteristics of the United States, or loyalty to the United States and defense of American political ideals. These ideals include but are not limited to independence, equality before the law, freedom of speech, democracy, and progress.

For example, according to the American Legion, Americanism is an ideology, or a belief in devotion, loyalty, or allegiance to the United States, or respect for its flag, its traditions, its customs, its culture, symbols, its institutions, or its form of government.

Theodore Roosevelt wrote that "Americanism is a question of spirit, conviction, and purpose, not of creed or birthplace."

The ideology has been central to a variety of fascist movements such as the Ku Klux Klan and the American Nazi Party. It has also been referred to by the American Communist Party with a slogan "Communism is Twentieth Century Americanism".

According to Wendy L. Wall in her 2008 book Inventing the "American Way": The Politics of Consensus from the New Deal to the Civil Rights Movement, Americanism was presented by a national propaganda campaign to contrast with Communism, and Fascism, during the Cold War, with the benefits of Americanism being promoted through the ideals of freedom and democracy.

Professor of political science at Clemson University C. Bradley Thompson stated that

The meaning of Americanism today, however, is very different. To the extent that the term is even still used, its meaning has been hijacked by both the Left and the Right. The Left most often identifies Americanism with multiculturalism, relativism, environmentalism, regulation, and welfarism — in other words, with progressivism. The Right typically identifies Americanism with Christianity, school prayer, tradition, family values, and community standards—in other words, with social conservatism. None of these values are, however, uniquely American. In fact, in one form or another, they all have a distinctly European provenance that is set in direct opposition to the native meaning of Americanism.