>>4135185They are a "social race". Look up racialization. Just because the concept of biological races in humans has been proven null and void doesn't mean that the ideas and stereotypes that it instilled in western societies completely disappeared.
Now whites don't think of themselves as a race in the sense that they don't consider themselves colored, they think of themselves as the norm, the basic version. Following that mindset, any deviation from the norm is, well, abnormal.
But again, since we're not talking about biological races, whiteness is something that refers to a certain appearance and a certain set of behaviors. A light skinned latino/afrodescendant/arab can be seen as white, but only if they adopt the codes of whiteness, i.e. dress "nicely", work an office job, appreciate classical european culture, etc. Conversely a person of european descent can be seen as not, or less white than they should be, think white trash or irish people in the 1800s-1900s, because of they behavior, way of life, tastes, etc.