Understanding Iran’s military structure: IRGC, Quds Force, Basij, and the Army. Who are they and what are their roles?

Within the dark and intricate structure of the Islamic Republic of Iran's military and security establishment, four dominant forces constitute the strength of the state: the Islamic Revolutionary Guard Corps (IRGC), its special arm the Quds Force, the volunteer Basij militia, and the regular Iranian Army, also referred to as Artesh.

Each has a separate origin, purpose, and command structure. Though all are nominally dedicated to the defense of Iran's sovereignty, their functions differ starkly in practice and ideology. Together, they create a layered and frequently overlapping system intended not only for external defense, but for survival of the regime, foreign manipulation, and domestic control.

The Islamic Revolutionary Guard Corps (IRGC)

Formed in the wake of the 1979 Islamic Revolution, the Islamic Revolutionary Guard Corps (Sepah-e Pasdaran-e Enqelab-e Islami) was founded by Ayatollah Khomeini to protect the revolution from internal as well as external enemies.

It was intended as a balance against the old Iranian military, which the new regime worried would still be loyal to the Shah or Western philosophy.

Unlike the Artesh, a professional and traditional military organisation, the IRGC is an ideologically motivated institution that owes its loyalty not to the government elected, but directly to the Supreme Leader of the Islamic Republic of Iran.

Its role is to safeguard Islamic values, propagate Iran's revolutionary ideology, and guarantee the survival of the regime.

Decades have seen the IRGC grow into a huge military-industrial complex. It has its own land forces, navy, aerospace unit (including Iran's missile program), intelligence unit, and cyber units. It economically dominates large sectors of the Iranian economy by means of front companies and state-sponsored foundations.

It is politically rooted to a great extent. Large numbers of members of the executive and judicial branches as well as the parliament have been IRGC veterans, and the IRGC is responsible for formulating national strategy.

Quds force

As the premier extraterritorial force of the IRGC, the Quds Force (Sepah-e Qods) conducts foreign operations, clandestine activities, and proxy warfare.

Its existence was formally recognised in the late 1980s, and its stature grew exponentially under General Qassem Soleimani, who died in a US drone attack in Baghdad in 2020.

The Quds force has provided the mission of exporting Iran's ideological and strategic interests outside of its borders. It offers weapons, finance, and training to a broad range of non-state actors and militant groups all across the Middle East, ranging from Hezbollah in Lebanon, Hamas and Islamic Jihad in Palestine, Shia militias in Iraq, the Houthis in Yemen, and pro-Assad forces in Syria.

With a history of strategic patience and asymmetric warfare, the Quds Force works through diplomatic covers, local militias, and covert networks. It is both a foreign policy instrument and a military force, combining intelligence operations with presence on the battlefield.

Basij

Basij, or Basij-e Mostaz'afin ("Mobilization of the Oppressed"), is an IRGC-controlled paramilitary volunteer militia.

Established in 1979 by the directive of Khomeini, the Basij was instrumental in the Iran-Iraq War, where thousands of Basij members were involved in human-wave attacks.

Nowadays, the Basij acts as an interior security force, responsible for policing moral behavior, repressing dissent, surveillance over universities and neighborhoods, and enlisting regime support.

It is highly integrated into civilian society, with units in schools, mosques, factories, and government departments.

In times of civil unrest—like the 2009 Green Movement protests and the nationwide protests in recent years—the Basij are usually the first line of response from the regime, making arrests, infiltrating demonstrations, and cracking down on crowds.

Though less heavily armed than regular army units, the Basij have strength in numbers, ideological indoctrination, and widespread grassroots presence. It also serves as a social control mechanism and vehicle for political mobilisation during election times.

Artesh

Officially referred to as the Artesh-e Jomhouri-ye Eslami-ye Iran, the Artesh is Iran's regular army, existing before the revolution.

Comprising four branches, they include Ground Forces, Air Force, Navy, and Air Defense. Following the revolution, the Artesh was suspicious to the clerical leadership and was purposefully undermined in favor of the IRGC.

Nevertheless, it continued to be the primary line of defense against conventional military threats, especially on Iran's borders and in the Persian Gulf.

In contrast to the IRGC, the Artesh is considered more professional and apolitical, with little role in Iran's internal politics or foreign escapades. It has fewer economic assets and is more dependent on the Ministry of Defense.

As much less ideologically charged, it is hampered by older equipment and limited modernization for decades of sanctions. The Artesh is also responsible for disaster relief, logistics, and border control operations, and frequently works together with the IRGC on large exercises, although tensions between the two branches continue.

Conclusion

Iran's military and security establishment is more than a defense establishment—it is a complex network of ideological, political, and coercive power intended to protect the Islamic Republic against all threats, foreign and domestic. The IRGC and related forces are the ideological core of the regime, while the Artesh fills conventional military roles.