When Tehran lashed out at its Gulf neighbours in the wake of US-Israeli attacks on Iran, GCC countries were deeply alarmed by the scale and direction of the strikes. Many Gulf governments and analysts describe the situation as a “nightmare scenario” they had worked hard to avoid.  Iranian strikes on their cities and infrastructure have generated shock, anger, and frustration. Reports indicate that in the first days of the war, Iran fired more than twice as many ballistic missiles and about 20 times as many drones at Gulf states than they did at Israel.

This shock around the region is likely compounded by the fact that Islamic teachings strongly condemn the killing of fellow Muslims and, more broadly, any unjust killing of innocents. Open aggression by a state that constantly invokes Islam feels religiously hypocritical as well as politically reckless. Iran’s emphasis on targeting civilian targets in the Gulf as has added to the outrage.

Classical Islamic sources treat the deliberate killing of a Muslim as a particularly grave sin. The Sunnah, an important source of Islamic law and teaching, contains multiple edicts from the sayings of the Prophet Mohammed and other founding fathers of Islam concerning not killing other Muslims, particularly civilians. At the same time, the Qur’an and mainstream jurists extend the prohibition more generally to killing any innocent person, whether Muslim or not, outside of a narrow context of selfdefence or a just war. Because of this, intraMuslim violence has often been framed in religious discourse as “fitna and fasad” (a state of evil and internal strife) that Muslims must avoid or minimise.

Iran’s leadership has frequently spoken in the language of Muslim unity, “defending Muslims,” and resisting Western and Israeli aggression. When that same state launches missiles and drones at neighbouring Gulf countries—killing or endangering Muslim civilians and striking states that had recently mediated on its behalf—people in the region experience not only strategic shock, but a sense also of religious betrayal and hypocrisy – munafiq. The cognitive dissonance between claims of Islamic solidarity and the reality of attacking other Muslim societies helps explain why reactions are not just angry, but also genuinely bewildered.

Arguably, the Iranian regime’s willingness to kill fellow Muslims has already been telegraphed by its willingness to harm its own people. The fatalities from the 2025–26 crackdown are difficult to quantify due to a severe information blackout and underreporting by authorities. However even the Iranian government admits that around 3,100 people were killed, including civilians and security forces, according to figures cited by state media and an official martyr foundation, and echoed in some international reports. Leaked local healthsystem figurescited by Time, the Guardian and Iran International suggest that between 30,000–36,500 protesters were killed during 8–9 January 2026 alone, with broader protestperiod tallies possibly above 30,000 nationwide. The International Center for Human Rights in Iran has claimed “at least 43,000” people killed in the protests as of 20 January 2026, based on its own field investigations and healthsystem sources.

Beyond its own borders, the Iranian regime also has a history of causing harm to fellow Muslims, whether supporting abusive militias in Iraq, or backing Assad’s mass violence in Syria. Since 1979, although Tehran has spoken publicly of Muslim unity, they have used their proxies across the region to deepen sectarian fault lines across the Muslim world, helping fuel cycles of retaliatory violence.

A Middle East Policy Analyst based in London commented: “Iran has, especially since 1979, caused enormous harm to Muslim lives and to regional relationships—sometimes in ways that far exceed Israel’s impact in specific arenas. Whether we’re discussing Iran’s role as a primary driver of violence in Iraq, Syria, Yemen, and Lebanon, their transnational “axis of resistance” of militias that operate inside other Muslim states, weakening sovereignty and deepening sectarian polarization, or indeed their actions against Gulf states… a great deal of Muslim blood has been spilled not in wars with Israel, but in Iranian-backed conflicts via proxies.”

Some commentaries explicitly say Iran “helped Assad kill approximately 500,000 Muslims”. As of March 2026, figures calculated by Human Rights Without Frontiers estimate that over one million Muslims have been killed by the Iranian regime since 1979, compared with 362,000 combined numbers for Muslims and terrorists killed by Israel since 1948.

This history will probably have added to the sense of betrayal and outrage felt across the Gulf when their neighbour Iran lashed out so viciously at civilian targets. After decades of talking a very big game about Muslim unity, the signs were in fact there all along that Tehran would have no hesitation in launching a barrage of missiles against Muslim countries who had tried to stay neutral, host dialogue, and offer deescalation, not war.

© Eurasia Review