Sociolinguistics takes such issues as language rights and language and nationalism into great consideration. Since there are different varieties of the same language within a country, people tend to favor one (usually standard) variety over the others. The role of sociolinguistics is to speak for the rights of speakers of all languages.
Crystal (2003, p. 21) notes that movements for minority language rights have been very important in many countries, including the USA. He claims that "in certain instances the decline of a language has been slowed, and occasionally (as in the case of Welsh) halted." Crystal also notes (p. 128) that some people are concerned with some "internal forces threatening the country's future identity."
The English language is viewed as a major factor in preserving "mutual intelligibility and American unity", especially in times when immigration is increasing at rapid rates. The 'official English' movement resulted from this viewpoint." Later, Crystal observes this position is "one of [...] elitism and discrimination." Thus speakers of minority languages would be denied "constitutional rights to freedom of self-expression and equal protection of laws" (p. 138).
Crystal refers to the statement on language rights issued by Linguistic Society of America in 1995:
Notwithstanding the multilingual history of the United States, the role of English as our common language has never been seriously questioned . [...] Nonetheless, promoting our common language need not, and should not, come at the cost of violating the rights of linguistic minorities (p. 139).
Given its multifaceted nature, sociolinguistics offers the community of language users a better understanding of policies hidden behind the veil of preservation of national identity through eliminating the linguistic diversity of this country.
Crystal, D. (2003). English as a Global Language (2nd ed.). Cambridge: Cambridge University Press.