Book excerpt: A provocative examination of how new realities of religion and migration are subtly challenging the very definition of what it means to be an American. Sociology professor Levitt argues that immigrants no longer trade one membership card for another, but stay close to their home countries, indelibly altering American religion and values with experiences and beliefs imported from Asia, Latin America and Africa. The book is a pointed response to Samuel Huntington's famous clash of civilisations thesis and looks at global religions' organisation for the first time.