With Russia standing accused of meddling in American politics and in Syria and Ukraine, new revelations about Russian doping in sports might seem anticlimactic. Yet the mountain of new evidence laid out by Richard McLaren, the Canadian lawyer appointed by the World Anti-Doping Agency (WADA) to investigate Russia's doping program, is astounding.

The case against Russia has been building over several years, with a striking turn last spring when the former head of the Russian anti-doping laboratory, Grigory Rodchenkov, described to the New York Times how he participated in a huge, state-supported operation at the 2014 Sochi Winter Olympics to swap out tainted urine samples from Russian athletes. WADA asked McLaren to investigate, and in July — on the eve of the Rio Olympics — he reported that his inquiry had established "beyond a reasonable doubt" that the Russian government, including its secret services, were involved in a far-ranging scheme to supply athletes with performance-enhancing drugs and covering it up. That led to barring more than a third of Russia's athletes from the Rio Games, and all Russians from the Paralympics.

Last week, McLaren issued the second part of his report, and it provided extensive evidence of extraordinary efforts by Russia's Ministry of Sport to cook up performance-enhancing drugs and ways to conceal them. These efforts benefited more than 1,000 athletes in at least 30 sports. "For years, international sports competitions have unknowingly been hijacked by the Russians," McLaren said when he presented his findings.

Russia's response was familiar: total denial that there ever was any "state-run" program coupled with pledges to combat doping and complaining that Russia is being unfairly singled out. More telling was its recent appointment of an athlete who had called last summer's suspension of Russian athletes "a blatant political order" as the new director of the Russian anti-doping agency.

This can't go on. McLaren's findings make it obvious that Russia — and any other country that participates in doping — must be excluded from international sport until WADA can establish that antidoping efforts are serious and honest.

FROM AN EDITORIAL IN THE NEW YORK TIMES