The US-Iran relations are structurally conflictual since the Islamic Revolution in 19791. The animosity is imbedded in the US-hostage crisis, freezing of Iranian assets and differing views on the security architecture of the Middle East. Despite overtures to normalize the bilateral relations from both sides, many issues impede these positive developments. Although there is convergence of interests on many areas, a few events from the past decade like regional peace process, terrorism, and most importantly, Iranian nuclear controversy continue to impact and cast shadows on the bilateral relations. The domestic politics in both countries and the US regional allies, especially, Israel and Saudi Arabia are other major challenges to their unfettered relations. However, lately the geopolitical position of Iran in the changing regional security environment, the phenomenon of ‘Islamic State’ and the agreed framework for a comprehensive nuclear deal raise the likelihood for a detente between Iran and the United States.