This much is certain: the Obama administration's Iran policy has been an utter disaster. The administration initially sought to engage (collaborate with) Iran--that is to say, to enter into a perfidious Grand Bargain with the Islamist power in order to pacify Pakistan and Afghanistan. The policy failed--miserably. Iran rebuffed Obama and pressed ahead with a foreign policy that is inherently imperialist. Iran's intentions--key word in international relations--are to overthrow the status quo, or power relations among nations, by destroying Israel and driving the United States from the Middle East. For starters. Ultimately, Iran intends to destroy the U.S. also.
The administration then fixated on sanctions to stop Iran. That, and countering Iran by backing Turkey's Islamist regime, which seeks to revive the Ottoman Empire, and the Muslim Brotherhood, which wants to take over the Middle East by installing Islamic republics across the region. Hence, the betrayal and abandonment of Egypt's President Hosni Mubarak and resulting Islamist capture of the Arab world's most populous nation and the pending, Islamist conquest of Syria, stirred up and supported by Washington.
Appeasement and engagement have made war with clerical fascist Iran inevitable--on Iran's terms--just as appeasement of Nazi Germany made war with it inevitable.