G'day Charlotte,
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If the subject is Black, or Asian, or Pacific Islander, or American Indian, or Alaska Native, or Hispanic, we say so. We add them to categories and to lists.
If they are white, rather than saying so, we look for a photo.
If we can't find a photo, we assume that the reader assumes the subject is white, because we haven't stated otherwise, because white is the default skin tone.{{fact}}
If the person knows which boat their ancestors arrived on, we might say they identify as "Norwegian American" or as "Irish American", then the reader can conclude the subject is white, but only if they know the demographics of Norway or Ireland.
Failing that, we assume that the person's race is irrelevant, and drop the issue completely [1].
I agree with you, but I feel like pointing out one little issue. Of course, here you've assumed every subject is American. This is not a criticism of you; it just means you're in the majority, 37.5% white or not.
A white actor is simply an actor, unless he's French. Sometimes he's from "San Francisco, CA", but rarely "San Francisco, California, United States of America". An actor from Paris is never just an actor, or even an actor from Paris --- he's a French actor, or an actor from Paris, France. This is because Americans realise that not everyone knows where Paris is, or which Paris is meant. The possibility that someone might not say "San Francisco? That means he's American!", however, is not worth discussing.
We all have our biases ...
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