Iran has been a critical player in the Syrian war since 2011, crafting a complex foreign policy and military strategy to preserve its Syrian ally. What have been the drivers of Iranian decision-making in this conflict? And how has Iranian strategy evolved over the course of the war? This article argues that the logic of deterrence has been fundamental not just for shaping the contours of Iran–Syria relations since the Islamic Revolution of 1979, but also for determining the overall trajectory of Iranian strategy in the Syrian war. The authors outline Iran's decision-making calculus and divide the country's strategy on Syria after the Arab Spring into four primary phases: 1) a ‘Basij’ strategy to establish local militias in Syria; 2) a regionalization strategy to incorporate transnational fighters and militias in the war effort; 3) an internationalization strategy to incorporate Russia and balance the United States; and 4) a post-ISIS deterrence strategy to balance against the United States, Turkey and Israel. Iran's Syria strategy progressively escalated in response to the possible defeat of its ally and the deterioration of its forward deterrence capacities against the United States and Israel. Today, the potential for direct inter-state conflict is rising as proxy warfare declines and Iran attempts to maintain the credibility of its forward deterrence.

What would the repercussions be of the U.S. pulling its support of Saudi Arabia? What is driving U.S. policy towards Saudi Arabia and what impacts do these policies have for America’s standing in the region and globally? Harvard’s Dr. Payam Mohseni and Dr. Qanta Ahmed weigh the pros and cons.

At such a delicate moment, when the risk of miscalculation and confrontation is growing, it is essential that policymakers in Washington gain a clearer understanding of Iran’s goals in Syria, which are not offensive but focus on deterring Israel and other major foreign stakeholders in Syria. Misperceptions of Iran’s strategic intentions could lead to military confrontation and an escalatory cycle — especially on the heels of U.S. President Donald Trump’s decision to pull out of the Iran nuclear agreement.

In mid-March, Iranian Foreign Minister Mohammad Javad Zarif traveled to Islamabad for a three-day visit, heading a 30-member Iranian delegation. During talks with Pakistani Prime Minister Shahid Khaqan Abbasi, Zarif pledged to increase bilateral trade between Iran and Pakistan from around $1.16 billion today to $5 billion by 2021. They also discussed other areas of cooperation. In an email interview, Payam Mohseni, the director of the Iran Project at the Harvard Kennedy School’s Belfer Center for Science and International Affairs, discusses how Iran and Pakistan’s mutual desire for a deeper relationship must contend with regional rivalries. 

High mistrust of Saudi Arabia by Iraqi Shi’as is hampering any meaningful outreach Saudi is undertaking toward Iraq and any policy of balancing Iraq and Iran will not succeed unless serious steps toward sectarian de-escalation is taken in the region. In order to bridge the gap, there needs to be broad religious dialogue to discuss the role of Shia’s and Sunnis in the region and forge a common space for the inclusion of both denominations. Major Grand Ayatollahs—the highest authorities in the Shi’a world—have taken positive steps of forbidding the ritual cursing of certain companions of the Prophet Muhammad and the early caliphs considered reverential to the Sunni community. In this endeavor the role of Ayatollah Sistani in Najaf will be crucial as he has a track record of promoting better relations between Shi’as and Sunnis and is an authoritative moderating figure who can reign in hardline elements in Iraq who might be opposed to a détente.

To end the year, Fareed Zakaria's CNN Global Briefing is running an exclusive series of quick takes this week from leading analysts. They will all be writing on the big issues to watch out for around the world in 2018. Iran was at the center of developments in a volatile Middle East throughout 2017. Expect more of the same in 2018, writes Payam Mohseni, Iran Project Director and Fellow for Iran Studies at Harvard’s Belfer Center.

On Friday, the United States reached a turning point in its relations with Iran. U.S. President Donald Trump forcefully denounced the Islamic Republic in a highly confrontational speech, threatening to upend the nuclear deal unless Congress amends it to make its terms more restrictive. By refusing to certify the accord, despite verification that Iran is in compliance, Trump essentially torpedoed the hard work that led to Washington’s recent opening to Tehran.

More than forty million Iranians surged to the polls and voted last Friday to choose their country’s future path: between one of engagement and diplomacy with the West and one based on a self-reliant economic populism. Although Iranians overwhelmingly chose the former option, the implications of these elections indicate that major battles over the fight for the next Supreme Leader and the political identity of the country loom on the horizon. In his latest article to the Washington Post, Payam Mohseni, Director of the Belfer Center's Iran Project, discusses the nature of the conservative campaign against President Hassan Rouhani and how, win or lose, it is the tenability and success of this conservative alliance that will significantly impact the future path that Iran takes—not simply the current re-election of Rouhani to the presidency.

Former President Mahmoud Ahmadinejad has registered to run in Iran’s presidential elections in May, despite having been advised not to do so by Supreme Leader Ayatollah Ali Khamenei. Payam Mohseni, director of the Iran Project at Harvard Kennedy School’s Belfer Center, emails CNN Fareed Zakaria's Global Briefing that Ahmadinejad’s entry is a genuine surprise, and that just registering could be seen as an act of defiance.

In 2006, in the midst of a fierce war between Israel and the Lebanese militant group Hezbollah, former U.S. Secretary of State Condoleezza Rice famously stated that the world was witnessing the “birth pangs of a new Middle East.” She was right—but not in the sense she had hoped. Instead of disempowering Hezbollah and its sponsor, Iran, the war only augmented the strength and prestige of what is known as the “axis of resistance,” a power bloc that includes Iran, Iraq, Syria, Hezbollah, and Hamas in Palestine.