Fred Kerley, Erriyon Knighton, Marvin Bracy Williams all suspended. All medalists in 2022. As is the case with Kenya, is the long-time dominance of sprints by the US based on natural ability or other elements? In fact, given the diversity of the human population is it even possible for 1 country to dominate a particular event for decades? Take football as an example, countries dominate in phases - Italy, Brazil, Germany, Spain, Argentina etc, but no one country is able to establish perpetual dominance. So when a country like Kenya, USA starts showing signs of what looks like indefinite dominance of long distance or sprints, should this serve as a red flag? Should we will still use genetics, technology, training facilities, environment all as excuses?