Final answer:
English is often referred to as a global lingua franca and functions as the de facto national language in the United States, although it is not legally the official language. Its widespread use is a result of historical expansion of the British Empire and the economic and cultural influence of the U.S. States laws regarding English as the official language have sparked debate over national identity and the rights of non-English speakers.
Step-by-step explanation:
English is considered to be a "global lingua franca" due to its widespread use and importance in international affairs, commerce, and culture. Although it is not officially the national language of the United States, over thirty states have designated English as their official language to promote assimilation and reduce costs associated with translation and bilingual education. This policy has been met with opposition from groups like the ACLU, which argue that such laws undermine the nation's diversity and the rights of non-English speakers.