The Holy See and the People’s Republic of China have never had formal diplomatic relations. But under Pope Francis, the two have become closer than at any time since the 1949 communist revolution. A Vatican conference May 21 on the history of the Church in China was the latest sign of this rapprochement – and a prominent illustration of the compromises that the Church has made in the process, the main one being “Sinicization,” i.e., making Catholicism compatible with socialism.