[graemep]

Secularism can mean a wide range of beliefs. A secularist might be a communist of fascist or a libertarian or a socialist or.....

How does race come into it at all? Religion is about belief and most religions welcome people of any race.

[Starman_Jones]

In American English, “race and religion” is an old-timey expression that’s typically used as a broad identifier in a melting-pot context, eg. “We are a nation of many nationalities, many races, many religions…” ~FDR

[Cthulhu_]

I suspect the comment means culture, which is frequently confused with race. But culture is also not uniform and will differ by individual etc.

[graemep]

Then maybe my other point applies. Secularism can exist within many cultures