Be it therefore resolved that the Society make known its opposition to such "English only" measures, on the grounds that they are based on misconceptions about the role of a common language in establishing political unity, and that they are inconsistent with basic American traditions of linguistic tolerance. As scholars with a professional interest in language, we affirm that:
The English language in America is not threatened. All evidence suggests that recent immigrants are overwhelmingly aware of the social and economic advantages of becoming proficient in English, and require no additional compulsion to learn the language.
American unity has never rested primarily on unity of language, but rather on common political and social ideals.
History shows that a common language cannot be imposed by force of law, and that attempts to do so usually create divisiveness and disunity. This has been the effect, for example, of the efforts of the English to impose the English language in Ireland, of Soviet efforts to impose the Russian language on non-Russian nationalities, and of Franco's efforts to impose Spanish on the Basques and Catalans.
It is to the economic and cultural advantage of the nation as a whole that its citizens should be proficient in more than one language, and to this end we should encourage both foreign language study for native English speakers, and programs that enable speakers with other linguistic backgrounds to maintain proficiency in those languages along with English.
http://www.lsadc.org/info/lsa-res-english.cfm