Sexual attraction plays an important part in long term relationships. Not even going to post you a link to a source, because there's too many on the internet to choose from.
If you're attracted to a Japanese woman, and start a relationship (Just a friendly one at first) with a Japanese woman based off of the attraction, who do you have more of a chance to fall in love with, a Japanese woman or a Jewish man? It's not really debatable...
But I honestly do understand the point you're making, and I understand where you're coming from. I'm not necessarily disagreeing with you, but more of simply adding to the truth.
Sexual attraction is intertwined with love, like it or not. It's the way it is.
Yes, you
CAN love a black girl, even if you are more sexually attracted to whites, but it's not probable, and it probably wouldn't last very long.
And I quote from number 4 of a top 10 list of why marriages fail:
"4. Sex Problems
Sex is an important part of marriage and the source of many marriage problems. Every marriage requires the act of consummation by sexual intercourse. Failure to consummate a marriage or problems with sexual frequency, quality, and infidelity are all common reasons for marriage failure and divorce."
Top 10 Reasons Marriages Fail | Divorce.com
Frankly, If you're banging a black chick, and want to be banging a Japanese chick, you're probably not too into the black chick sexually. Thus, if you're not too into the black chick sexually, (no pun intended) then it could probably lead to not being into her at all.
All in all, if you're attracted to Japanese women, and that's really all you go for, then you don't really have a chance to fall in love with any other type of women in the first place.
Sorry for unnecessary elaboration, I just like this subject.