On August 25 Archbishop Carlo Maria Viganò published an eleven-page letter in which he accused Pope Francis of ignoring and covering up evidence of sexual abuse in the Catholic Church and called for his resignation. It was a declaration of civil war by the church’s conservative wing. Viganò is a former apostolic nuncio to the US, a prominent member of the Roman Curia—the central governing body of the Holy See—and one of the most skilled practitioners of brass-knuckle Vatican power politics. He was the central figure in the 2012 scandal that involved documents leaked by Pope Benedict XVI’s personal butler, including letters Viganò wrote about corruption in Vatican finances, and that contributed to Benedict’s startling decision to abdicate the following year. Angry at not having been made a cardinal and alarmed by Francis’s supposedly liberal tendencies, Viganò seems determined to take out the pope.