The president of Michigan State has resigned under pressure.

So have several members of the board of U.S.A. Gymnastics.

Now the heat turns to full boil on the United States Olympic Committee, whose officials did not even bother to sit in the Michigan courtroom to hear the grim, brave testimony of more than 150 girls and women, some of them Olympic champions, about how Dr. Lawrence G. Nassar molested them when he was supposed to be healing them.

Scott Blackmun, the chief executive of the Olympic committee, apologized in an open letter on Wednesday, saying the committee “should have been there to hear it in person, and I am deeply sorry that did not happen.”

The Olympic committee had been expecting to celebrate its medal haul at the Winter Games, which begin in two weeks in South Korea. Instead, it finds itself defending accusations that it did too little too late; that it was more concerned with protecting its image than its athletes; and that it did not even offer solace to victims, much less safeguards.