For roughly three decades, making sure athletes participated in the biggest events regardless of the world’s never-ending military and political battles has been a nearly sacrosanct tenet of international sports.

Wars broke out. Authoritarian nations with egregious records on human rights hosted major events. There were massive doping scandals. And through it all, boycotts and bans on participation all but disappeared from the sports landscape.

That principle — staging truly global competitions and not holding athletes responsible for the world’s ills — began to crumble after Russia’s invasion of Ukraine in late February. It will be on hiatus starting Monday, when Wimbledon opens without the world No. 1, Daniil Medvedev, and the rest of the tennis players from Russia and Belarus, who have been barred from participating.