This is a really fraught issue in the US, because post-9/11 a lot of racial profiling has focused on people of Middle Eastern or Central Asian descent, and there have been a number of court decisions that ruled such people were "white" and thus not protected by US anti-discrimination laws, which have historically focused on other communities.

I suspect this is related to the census protests by Arab and Iranian Americans--the reasons why people of Middle Eastern heritage have legally been considered white historically, is tied up in explicitly racist attitudes (and religious bigotry) about immigration.

I can't seem to find a good overview of the history, but this factsheet on Arab American immigration (http://www.pbs.org/itvs/caughtinthecrossfire/arab_americans.html) touches on some of it.