Washington and Moscow agree on very little. This week, diplomats from both countries accused Annalena Baerbock, president of the United Nations General Assembly, of exceeding her authority in the selection of the next U.N. secretary-general. The Trump administration is right. Baerbock has turned a useful exercise in public scrutiny into an attempt to decide which candidates the Security Council may consider.

Article 97 of the U.N. Charter leaves little room for confusion. The secretary-general is appointed by the General Assembly upon the recommendation of the Security Council. The 15 council members narrow the field through closed straw polls until a candidate receives at least nine votes without a veto from the United States, Russia, China, Britain, or France. The General Assembly then votes on that candidate.