Well, at that point, I wasn't actually talking about Americans. There aren't all that many "Americans of East African" descent. A few, and I'll certainly cheer for them, but we're not going to become a sustainable distance power on the legs of those few.
I was talking worldwide. World's best times. As in, the world's best 5k and 10k times are pretty much dominated by Ethiopians and Kenyans.
That's very different from in the U.S. Distance teams across the U.S. are very, very white. letsrun is very white. Part of why mid d is better is precisely because it's not as white in the U.S.
I didn't say anything about what we should shift our attention away from. I sure as hell don't want any attention shifted away from any track events. Shifted away from? I don't know...football? baseball? poker? Lady Gaga? Xbox? Masturbation?
I don't know that the focus of American fans should depend on race/genetics. But does it, to some extent?
I think we naturally cheer for/aspire to become people who look/act/talk like us. That's not necessarily such an ugly thing (unless, of course, it becomes an ugly thing). We should definitely appreciate great athletic feats, regardless of race/genetics. But still, Chinese people cheer for Yao Ming. So what? Fewer black people are going to be as excited about swimming as track. So what? I'm a skinny short white guy who loves basketball, and I have a severe man-crush on Steve Nash. So what?
The beauty of mid d? Little Latino kid has Manzano. Big Latino kid has Juantorena. And so on.