Is the US already at war with Iran? In "America's Secret War", Vanguard correspondent Mariana van Zeller travels to the Iraq-Iran border to investigate claims that the United States is supporting militant groups that are attacking Iran. In the rugged Qandil mountains, she meets with up with anti-Iranian guerillas who have been launching deadly raids against the Islamic Republic. A good percentage of the fighters are women, and Mariana accompanies a small group of them through what many believe has become the frontline of the US's secret war with Iran.