Why the U.S. and Iran are caught in 'cycle of confrontation'

Over the past week, the difficult relationship between the U.S. and Iran has become even more strained. The Trump administration warned of severe consequences for any Iranian aggression, while Iran has threatened to exceed limits on its nuclear program. On Tuesday, Saudi Arabia said rebels in Yemen believed to be backed by Iran staged an attack. Judy Woodruff talks to Nick Schifrin for more.