All most Americans expect is that existing laws be enforced. So, to answer your question, "Who is American?", or more to the point, "Who should be allowed in America?", the popular answer would be, "Those who entered the U.S. legally, and maintain legal status while in the country, whether they become citizens, or resident aliens, here on visas, etc. . . . those people are welcome in the United States." Conversely, those who enter the country illegally, and/or remain in the country after their legal status expires . . . those people are the ones that most Americans object to. Personally, I don't care if people live in an adjoining country and LEGALLY commute into U.S. each day to work a bonafide job here and then return home -- they are obeying ours laws and I have no problem with their doing that.
The concern is not, as the opposition wants to claim, that the newcomers are non-white. It is that they violate the laws of the U.S. by coming here illegally and circumvent the established process for legal immigration.
True, another concern is that America stay America. We have a dominant language that almost all Americans speak, which helps to unify us as a nation. I don't care if legal residents speak another language as well, but I don't think it is reasonable for people to move here and then expect their host nation to change to accommodate them. Likewise, we have our traditions and holidays, or American version of history and heroes (we are not alone in that, as all nations/peoples interpret events in a way that honors themselves), and we should not have our American ways supplanted in order to satisfy newcomers. As often happens, the dominant culture often adopts some of the ways of other groups (e.g., the cities and states in U.S. that adopted Indian names -- as in my native Ohio; words borrowed from languages other than English and are in common usage by English-speaking Americans).
So, in a way, we do honor other cultures. But to be REQUIRED to do so in order to make the newcomers more comfortable . . . I don't see that as necessary or as a reasonable expectation. If, for example, I relocated to Italy, I would not expect or demand that Italians change to satisfy me or make their country feel more like my home in U.S. No, if I go there, I expect to deal with their culture as-is and to put forth the effort myself to acclimate to the host culture. True, it would be great to have Italians speak English to me (since I don't speak Italian), but I wouldn't get hostile and demand that everyone and everything communicate to me in English.
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