I think there's some confusion going on here from two different uses of the term "Caucasian".

From Wikipedia:

The Caucasian race (also Caucasoid or Europid) is a grouping of human beings historically regarded as a biological taxon, which, depending on which of the historical race classifications is used, has usually included ancient and modern populations from Europe, Western Asia, Central Asia, South Asia, North Africa, and the Horn of Africa.

[...]

In the United States, the root term Caucasian is often used, both colloquially and by the US Census Bureau, as a synonym for white. This usage is considered erroneous by anthropologists and other scientists, who note that it conflates an anthropologically valid category (Caucasoid) with the social construct of the "white race". The conflation of Caucasian with white is also demographically misleading since the category Caucasoid has sometimes been considered to include various populations, such as South Asians and North Africans, that are not considered white in a social sense.