I suppose its because the mainstream American definition of racism is different than mine, but I don't see anything explicitly racist in the statement. Wanting your own group to procreate and thrive doesn't necessarily mean you consider other races to be inferior or have prejudices against them.
Yeah, that's kind of a racist sentiment.
^ Seriously.
Not to mention that even if that was a reasonable attitude to have, "caucasian" isn't a thing. What's caucasian culture, for example?
goat herding and fire jumping.