The History of Iran in Syria
Throughout the war in Syria, Iran has emerged as a dominant foreign influence on the most bloody and catastrophic conflict the region has known. Tehran is relentlessly applying its financial, military, and economic resources to prop up Syrian President Bashar al-Assad's regime, regardless of its atrocities. Half of a decade into the Syrian war, Iran has established a major foothold in the country, becoming an undeniable feature of any likely post-war landscape.
The Iran-Syria alliance dates to the first years after the Iranian Revolution (1979). Syria was the only Arab country that have explicitly stood by Iran during the bloody Iran–Iraq War (1980–88). While Syria is supposedly secular, the alliance has been cemented with a measure of religious and ideological affinity: Syria's Alawite leadership, was acknowledged as Shia by the Lebanese Shiite cleric Musa al-Sadr in the 1970s, and important Shia shrines and memorials are located in Damascus. Most importantly, both sides declare themselves as fully committed to "resistance" against Israel.
The strategic pact between these two countries deepened when Bashar al-Assad inherited Syria's presidency from his father (2000). Iran and Lebanese Hezbollah leader, Hasan Nasrallah, became guardians and tutors of the unexperienced ruler. Iran became involved in Syria's most sensitive defense affairs and used Syrian territory to transfer advanced arms to Hezbollah.
Since the onset of the conflict in 2011, Syria became increasingly dependent on Iran. The Quds Force, the elite extraterritorial arm of the Iranian Islamic Revolutionary Guard Corps (IRGC), formerly led by General Qassem Soleimani and currently under the command of Ismail Qaani, became an integrated component of the regime’s backbone, and spearheaded foreign involvement on the ground.
At first, the Iranians tried to prop up the regime and prevent the fall of Damascus and the strategic northern cities into the hands of the rebels, with limited active involvement. Iran supported the regime by arms transfers, economic aid, and military advice.
Towards mid-2015, mounting successes of the Islamic State, Jabhat Al-Nusra and other rebel groups cast serious doubts on the ability of the Assad regime to survive. Iran, seeing Assad’s survival as a strategic interest, intensified its support of the regime and escalated its involvement in Syria. Iran's active involvement was bolstered by the deployment of large number of Shiite foreign fighters: Lebanese Hezbollah as well as Afghan, Iraqi and Pakistani militias.
Thus, Iran has had a crucial part—alongside Russia—in changing the course of the war in favor of the Assad regime. Shiite fighters headed the fighting that brought major territorial gains against the opposition, most notably Aleppo (late 2016). They have turned their attention to Eastern Syria only lately, coming into limited conflict with Western-backed militias fighting against the Islamic State.
Iran's escalating involvement in Syria over the course of the conflict is meant not only to support an ally, but also to maintain its role in the future. Iran's tremendous investments of financial, material, and human resources in Syria are an indication that the Iranian regime sees its presence in Syria as a long-term affair.