The irony of all this is that even now... with this supposed "U.S. running resurgence" is the following:
1) The US population is well over 300 million people now.
2) We are one of the most technologically-advanced, modern societies in the world. In other words, we've got the best training facilities. Or at least we think we do.
3) Almost every high school has a cross-country and track team.
4) You need no talent to join these cross-country and track teams. There is no barrier to entry. So any HS student in our massively-populated country can join and compete in cross-country or track immediately.
5) Kenya and Ethiopia, on the other hand, probably have 30 to 50 times more depth at distance running than the U.S... with a much, much smaller population. What's more, Kenya and Ethiopia are "developing" nations.
So you can talk "resurgence" all you want. The bottom line is if you're any good, you're gonna get absolutely spanked by the East Africans sooner or later.
Just look at the top 100 marathon times this year and see how many are U.S. born Americans... and how many are East Africans.
The only way any U.S. born American will ever medal in a distance event - unless something radical happens in the near future - is if at least 2-3 East Africans competing in any given major race get injured, sick, or run a really crappy race. They are simply too good compared to us.
It's a joke.
Even all these "sub 9" guys in HS would probably get steamrolled by a 14 year old Kenyan wearing his school uniform and carrying books in one arm.