War on Iran: How the Islamic Revolutionary Guard Corps underpins the republic

What Happened

Middle East Eye published an explainer detailing the structure and role of Iran's Islamic Revolutionary Guard Corps (IRGC), which it describes as underpinning the Islamic Republic and directing much of Iran's response to US and Israeli attacks this year. The IRGC was founded in March 1979 by commanders of conservative militias that helped overthrow Shah Reza Pahlavi, and today has five arms: a ground army, an air force, a navy, the elite overseas Quds Force, and the volunteer paramilitary Basij. The article estimates the IRGC has 150,000-plus active personnel, plus Basij volunteers ranging from 100,000 to 1m, compared with Iran's regular Artesh army of around 600,000 troops. It controls Iran's ballistic missiles, is tasked with safeguarding border security and nuclear facilities, and holds an estimated 50 percent of revenues from Iran's oil sector through government contracts and monopolies.

Key Actors

Why It Matters

The IRGC's control over ballistic missiles, nuclear facility security, and the Quds Force proxy network makes it central to Iran's ability to strike Israel, influence regional conflicts, and withstand external pressure. Its economic monopolies and domestic repression through Basij also entrench regime survival, meaning any effort to change Iranian behavior militarily or through sanctions must account for the IRGC's role as a state within a state.

Watch For

Watch for IRGC ballistic missile activity against Israel, Quds Force resupply to Hezbollah and other proxies following the collapse of the Assad supply channel in December 2024, and any Basij crackdowns on renewed domestic protests. Also monitor IAEA reporting on nuclear facilities guarded by the IRGC and any shifts in its estimated oil revenue share under sanctions.