I honestly think the US is shining in these games for a couple reasons.
1) It’s been a slow steady progression over the past two decades to get this many Americans competing for medals on the global level. Our younger runners are training harder (and more importantly more consistent) than ever and more importantly, smarter than we ever have…especially compared to the 80’s and 90’s. We have great coaches at all levels (club, HS, college, pros). And even coaches that don’t know sh#t about distance running now have full access to training, nutrition, etc via the internet and clinics. Plus, we are one of the largest countries in the world with the best resources for athletics. We should be a dominant force in all sports, track and field included.
2) More so, I feel there are less dopers competing in global championships than we’ve seen in 40 years. The playing field has leveled for the US. While I believe many of these athletes are definitely on supplements (beta-alanine, etc) the number of athletes using illegal substances has decreased. Over the past decade the testing has increased significantly, while the penalties for getting busted has stiffened. There’s no question that athletes will continue to dope, but the risk is slowly, but surely becoming bigger than the reward.
3) The Africans are not feared anymore. Outside of the marathon (where the bulk of doping incidents are occurring), the Africans have proven to be human. For years the Africans were given the pass when talks of doping were brought to the forefront. The belief was their upbringing, genetics, geography made them better runners, not doping. Wrong. Less African doping definitely gives others opportunities for medals that weren’t there 30 years ago. Now even little unknowns like Kenneth Rooks can bring it to these guys!!!