Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. Mattis: US Not Pursuing Regime Change in Iran by Reuters WASHINGTON -- The United States has not instituted a policy of regime change or collapse in Iran, U.S. Defense Secretary Jim Mattis said on Friday, telling reporters that the goal was still to change Iran's behavior in the Middle East. Asked whether the Trump administration had created a regime change or collapse policy, Mattis said: "There's none that's been instituted." "We need them to change their behavior on a number of threats that they can pose with their military, with their secret services, with their surrogates and with their proxies," he added.