You’d think a country with the resources of the US would go out of its way to give its own runners a fighting chance by being militant in funding waves of research and blitzing the testing of athletes, globally.
but what goes around comes around, and their own dirty laundry would end up in public as well undermining public support of their mission. eg. Marion Jones.
so what does everyone do? the bare minimum to fight the worst offenders, and try to be the best in the “marginal cheating and blind eye” category. The problem? some countries are better at marginal cheating than you, so the Olympic year becomes a test of who can get away with the most, come off the sauce, and retain the advantage in competition.
see: Italian Athletics at Tokyo Olympics