AP Photo

CHEN GUANGCHENG, one of China’s best-known and bravest human rights activists, had been illegally and unjustly kept under house arrest in his village for 19 months when he somehow escaped last Sunday. He made his way to Beijing, and though his whereabouts are unconfirmed, activists reported Friday that he was under the protection of the U.S. Embassy. The State Department refused to respond to questions about him. If the activists are right, as seems likely, the Obama administration faces difficult conversations with the Chinese government at a sensitive moment. But the principle it should adhere to is clear: It must be prepared to offer Mr. Chen refuge if he seeks it and refuse to allow his return to state custody — either official or unofficial.