Chalker was a vocal critic of United States policy towards Iran, and in 1979 she was arrested along with other activists for hanging a "U.S. Imperialism Get Your Bloody Hands Off Iran" banner on the Washington Monument. She traveled to Tehran as a member of the "Send the Shah Back—Hands Off Iran Delegation" in support of the Iranian Revolution and the occupation of the United States embassy in Iran. After her return to the United States, she and Eileen Schnitger (a fellow member of the Feminist Women's Health Center) disrupted the Women's National Powerlifting Championships while wearing "Send the Shah Back" t-shirts.