It is problematic to characterize any ethnic group, as in doing so one runs the risk of stereotyping and discrimination. Also, ethnicity itself is a somewhat problematic concept, especially in today's mobile society in which people from many different cultures and national origins live together. Italian-Americans, Polish-Americans, Scandinavian-Americans and many others would all count as "white" or "Caucasian".
The label of White Anglo-Saxon Protestant (WASP) generally referred to middle and upper class people who immigrated to America from England and Scotland in the eighteenth and nineteenth centuries. Compared to other groups in the United States, they were relatively well-off, well-educated, had a strong work ethic and a culture of restraint and delayed gratification Max Weber's The Protestant Ethic and the Spirit of Capitalism theorizes an inherent connection between this sort of Protestant ideology and successful capitalism.
Thank you, and well said. You mentioned Italian-American, Polish-American, Scandinavian-Americans, etc. but none of these groups has reached parity with the dominant Anglo group in economic status and political power, none has entered fully into primary relations with the Anglo group, and none has completely lost its cultural form trhough assimilation.
Marger, M. (2012) Race & Ethnic Relations American and Global Perspectives (9th ed.). Belmont, CA: Wadsworth.