Iran’s political and military structures are unique, with power concentrated in the supreme leader, who sits at the top of a multi-layered system of elected institutions, unelected bodies and parallel military forces.
As the US escalates threats to strike Iran, and President Donald Trump builds a case against Tehran by accusing it of developing missiles capable of reaching Europe and the US, attention is increasingly focused on how the Islamic Republic itself functions.
For decades, Iran has developed a network of allied armed groups stretching from the Mediterranean to the Red Sea and beyond, alongside an extensive ballistic missile project and a controversial nuclear programme. Together, these form the backbone of its defence posture and raise a central question: could the regime survive a major military attack?
Here is a closer look at how Iran’s political and military system works:
Parallel militaries
Iran operates two parallel military forces, a structure created after the 1979 revolution to protect the country and the ruling system.
Regular army
Iran's conventional military predates the 1979 revolution. It features ground forces, a navy, an air force and air defence units.
The army handles traditional defence – borders, territorial integrity and conventional warfare – but it is believed to be underfunded and viewed with some distrust by the regime.
Islamic Revolutionary Guard Corps
The IRGC is the regime's ideological army, founded after the revolution specifically to protect the Islamic system. It operates as a vast parallel military with its own ground forces, navy, air force, missile programme and intelligence services.
The IRGC is wealthier, better equipped and more politically powerful than the regular army. It controls major sectors of Iran's economy, from construction to energy and telecoms, effectively functioning as a state within a state. It answers directly to the supreme leader, not the president or parliament.
Within the IRGC, the most important subunit is the Quds Force, its foreign operations arm. It trains, funds and directs Iran's network of proxy militias across the region, including Hezbollah in Lebanon, the Houthis in Yemen and various militias in Iraq.
The Basij
The Basij began as a volunteer militia during the Iran-Iraq War (1980-1988), when poorly trained fighters were sent into battle in large numbers. After the war, it was absorbed into the IRGC as a subordinate paramilitary force.
Today, the Basij primarily serves as an internal security and social control tool. Its members suppress protests, monitor neighbourhoods, enforce dress codes and moral laws, and act as ideological enforcers.
Layers of authority
Iran is both a republic and a theocracy. It has elections, a parliament and a president, but unelected religious authorities hold ultimate power. The elected and unelected systems operate side by side, with the unelected layer prevailing in any conflict.
The supreme leader
Ayatollah Ali Khamenei has held the position since 1989. As commander-in-chief of all armed forces, he sets the broad direction of foreign and domestic policy, controls the official narrative and appoints key figures across almost every major institution. In theory, he is accountable only to Islamic law.
The position was created by the revolutionary concept of Velayat-e Faqih, or Guardianship of the Islamic Jurist, developed by Ayatollah Ruhollah Khomeini, which holds that a supreme Islamic scholar should govern society until the return of the Hidden Imam. It fuses religious authority with political power.
The Assembly of Experts
The 88-member body of Islamic scholars is elected by the public every eight years, but candidates are pre-screened by another body, the Guardian Council, so only approved clerics can run.
On paper, it has enormous authority: it selects and can theoretically remove the supreme leader. In practice, it largely manages succession planning and meets only a few days each year.
The Guardian Council
The council has 12 members – six Islamic jurists appointed by the supreme leader and six others nominated by the judiciary and approved by parliament.
It has two main powers: it vets all legislation passed by parliament to ensure it complies with Islamic law and the constitution, and it screens all candidates for elections, including for the presidency and parliament.
The president
Elected by popular vote every four years, the president leads the executive branch, controls the cabinet and manages day-to-day governance and the economy. However, the role has no authority over military policy and cannot override the supreme leader.
Reformist presidents often seen their agendas blocked. Masoud Pezeshkian was elected President in 2024. He has influenced diplomatic tone and domestic policy priorities but does not hold ultimate power.
The Parliament
Iran’s parliament has 290 elected members serving four-year terms. It passes legislation, approves the budget and can impeach ministers. However, all legislation is subject to Guardian Council review and can be vetoed.
The parliament has real but constrained power as it is often described as a genuine site of political debate and factional struggle, but always within limits.
The Expediency Council
This body mediates disputes between parliament and the Guardian Council when they cannot agree. It also advises the supreme leader on long-term policy. All members are appointed by the supreme leader.
The Judiciary
The head of the judiciary is appointed by the supreme leader for a five-year term. This gives the leader indirect control over the courts, prosecutors and the legal system as a whole.
The judiciary also nominates half the members of the Guardian Council, which gives it influence not just over legal matters, but over the political system itself.
