Shirley Sotloff said in the video plea that she had learned about Islam since her son’s capture a year ago in Syria, including that “no individual should be held responsible for the sins of others.” She stressed that her son had no control over the U.S. government.

“I’ve always learned that you, the caliph, can grant amnesty,” she said. “I ask you to please release my child.”

Her language throughout the video was deliberate. In presenting her son as a reporter bearing witness to a fight against tyrants, the mother was invoking a powerful idea in Islam, said Patrick M. Skinner, director of special projects for the Soufan Group, a security consulting company.

“The way that translates in Arabic is really powerful,” he said. “Tyrant is a really, really big image in Islamic history. They’re always fighting against tyrants. The Syrian civil war was to rise up against a tyrant.”