The president insists she backs democratic norms, but individual liberty is vanishing. Mexican President Claudia Sheinbaum says the "audience rights" initiative she announced last month is designed to protect the public from fake news. But by making a government agency the arbiter of the truth, the president's effort greenlights censorship.

Journalists, writers, intellectuals and entrepreneurs are alarmed. The slow strangulation of democratic pluralism in Mexico by Ms. Sheinbaum and her Morena party started with President Andrés Manuel López Obrador (2018-24), also known as AMLO.

He governed as a classic populist, expanding welfare rolls to buy loyalty at the ballot box. But as someone who came up in politics during the 71-year rule of the repressive Institutional Revolutionary Party, he understood that perpetual power for Morena required more.