Immediately after the results were announced, peaceful demonstrations began and quickly grew in size, initially overwhelming and paralyzing the regime’s security forces. In the early going, riot police provided the first line of security, beating back advancing demonstrators with tear gas and brute force. As images of violence spread, the protests grew and soon were the largest Iran had witnessed since the Islamic Revolution, dwarfing the 1999 student protests that were their direct antecedent. The regime moved to block internet access in a bid to thwart the protestors’ ability to organize and undertook a censorship campaign to suppress images of the violence from circulating in Iran and abroad, but the protests continued to grow and become increasingly chaotic and violent in response to the regime’s aggression.

Mousavi had called for a protest march on June 15, 2009, but as the demonstrations spiraled out of control, he withdrew his support for the event both to preserve the regime’s stability and not run afoul of Khamenei and the security apparatus, who warned him that any large-scale protests would be deemed illegal. Despite his efforts, the groundswell of popular resentment carried on unabated, and more than a million Iranians took to the streets that day, indicating a leaderless, grassroots uprising was underway. Mousavi ultimately decided to join the protests as part of the mass of demonstrators rather than at the forefront. The protestors’ ire was largely aimed at Ahmadinejad. However, over the day, they increasingly broke the taboo of challenging Khamenei and the corrupt Islamic Republican system, with spontaneous chants of “death to the dictator” breaking out quietly and growing increasingly frequent and loud.

The mounting demonstrations over the disputed election results posed a clear crisis of legitimacy for Khamenei and the regime. However, Khamenei opted to respond with repression rather than give in to the demands to nullify and redo the election. By the end of the day on June 15, the IRGC, tasked with the nationwide response to the protests, dispatched units of both plainclothes and uniformed basijis and Ansar-e Hezbollah volunteers to confront the protestors. With many riding motorcycles through the crowds, scenes abounded of basijis beating protestors with clubs to disperse them. There were numerous reports of indiscriminate gunfire during the demonstrations, and the protestors became increasingly violent. At least 30 protestors died in clashes around the country on June 15. The following day, the regime moved to arrest various leading reformist and human rights leaders to curb the movement’s organizational capabilities.

Buoyed by the demonstrators’ growing strength and refusal to be cowed, Mousavi opted to increasingly take on the leadership mantle of the protest movement, directing his supporters to adopt the color green due to its resonance in Islam. This suggested that the burgeoning “Green Movement” was acting in accordance with and inspired by Islamic principles, challenging the hardliners’ hegemonic claims to be the authentic representatives of Islam.

Clashes continued in the ensuing days as Mousavi supporters held further demonstrations to challenge the election results and mourn those killed. In contrast, supporters of Ahmadinejad and Khamenei staged counterprotests. On Friday, June 19, Khamenei gave an incendiary Friday prayer sermon in which he reiterated that the results were valid and warned of an impending crackdown. To intimidate Mousavi, Khamenei warned that opposition leaders who failed to rein in the demonstrations “would be responsible for bloodshed and chaos.” Khamenei insisted it would have been impossible to rig a victory of Ahmadinejad’s wide margin and stated that the president could be chosen only through the ballot box and not through street protests. Finally, he deflected blame for the crisis onto Iran’s enemies, whom he claimed were seeking to foment unrest by depicting Ahmadinejad’s “definitive” victory as “doubtful.” Khamenei typically preferred to operate behind the scenes. However, his sermon represented him taking sides with the hardline faction against the reformists in an unprecedented public way and effectively ruling out any hopes for a compromise. Khamenei had made clear that he viewed continued unrest over the election results as a foreign-backed plot that threatened the fabric of the Islamic Republican system.

Despite Khamenei’s attempt to intimidate the Green Movement and its leaders and warnings from the police and IRGC, thousands of protestors took to the streets the day after Khamenei’s sermon, and sporadic demonstrations continued over the following months. Khamenei tasked the IRGC with coordinating the nationwide response to quelling the unrest as part of its overarching raison d’etre to safeguard the Islamic Revolution against foreign and domestic threats. The IRGC seized on Khamenei’s effective declaration of war on the protests to increase their ruthlessness and brutality in suppressing the demonstrations. On June 20, the day after Khamenei’s sermon, a basiji shot into a crowd of demonstrators and killed a 26-year-old Iranian woman, Neda Agha-Soltani. Video footage of her death rapidly spread through Iran and worldwide, provoking outrage over the regime’s wanton excesses. Neda became an enduring symbol of the “Green Movement,” highlighting the citizenry’s willingness to risk their lives for greater rights and freedoms. Recognizing the stark contrast between the ostensible principles of the Islamic Revolution and its actual treatment of its citizens, the regime sought to deflect blame for Neda’s killing onto assorted enemies such as the MEK, Zionists, and the foreign media.

The continued growth of the protest movement in the face of increased repression heightened Khamenei and the IRGC’s paranoia, and they saw evidence of foreign plots and a conspiracy to impose a velvet revolution all around them. The Obama administration was sensitive to the history of Western intervention in Iranian affairs and did not want to give the regime ammunition to delegitimize the organic protest movement following the rigged election. In the early days of the protests, as scenes of the regime’s brutality emerged, President Obama gave a tepid response, calling upon the Islamic Republic’s regime to uphold the rule of law and human rights but stopping short of calling the election fraudulent or laying out consequences for egregious abuses by the regime. Despite Obama’s caution, IRGC officials continued to accuse the demonstrators of cooperating with the U.S. and other enemies of Iran in pursuit of regime change, justifying their increasingly harsh crackdown.

In the ensuing weeks, the protests dwindled under the IRGC-directed suppression effort enforced by riot police and basijis. It became increasingly clear that Khamenei would not compromise under pressure and was willing to kill and torture his opponents to maintain his iron grip and clear the streets of protestors. During the Islamic Revolution, Khamenei witnessed the Shah admit to past excesses to pacify the swelling protests. However, the Shah’s gambit backfired and only emboldened the protestors, culminating in his removal from power. Determined not to repeat the Shah’s mistakes, Khamenei became increasingly reluctant to give an inch to the protestors and relied more heavily on the IRGC and the sprawling security apparatus under his control. The regime’s brutal response included efforts to control the internet and censor the dissemination of imagery that would paint the regime in a negative light, arrests of journalists and Green Movement leaders, mass arrests of thousands of protestors and activist leaders, reports of torture and rape under regime custody, and show trials and forced confessions of opposition activists. Opposition leaders claimed at least 70 citizens were killed during the protests or in regime custody, although the true death toll was likely higher.

While the IRGC-led suppression effort succeeded in dissipating the protests, the Green Movement persisted for months after the fraudulent election. To prevent protests around Ahmadinejad’s second inauguration, the regime conducted show trials of over 140 prominent reformist politicians, journalists, academics, and activists on August 1, 2009. The defendants had suffered torture at the hands of Iranian security forces, and many offered coerced confessions of plotting a color revolution at the behest of foreign powers. Despite the farcical nature of the proceedings, Khamenei and the security apparatus used the trials as a pretext to further delegitimize reformism and push those with reformist predilections further away from the centers of power within the Islamic Republic, which was increasingly concentrated in the hands of hardliners aligned with Khamenei’s principlist ideology.

Public holidays and national days of commemoration provided the impetus for the resumption of widespread demonstrations, which increasingly challenged the legitimacy of Khamenei and the revolutionary system rather than just the stolen election. Each wave of protest was met in kind by increasingly wanton repression, culminating in a showdown between the Green Movement and security forces on December 27, 2009, the day of Ashura. During the period leading up to the Islamic Revolution, Khomeini’s followers used the symbolism of Ashura to muster the fiercest and most widespread resistance to the Shah’s rule. The Green Movement now sought to coopt that same symbolism to galvanize opposition to Khamenei and the revolutionary system he presided over. He argued that the Islamic Republic represented the latest corrupt iteration of dictatorship despite its Islamic veneer.

The Ashura protests in 2009 coincided with the culmination of a seven-day mourning period for the death of Ayatollah Montazeri, Khomeini’s former heir apparent and the senior-most ayatollah in Iran at the time of his death. Montazeri’s criticisms of the excesses of the revolutionary regime made him the spiritual leader of Iran’s reformist movement, and his denunciations of the fraudulent election buoyed the Green Movement and helped counteract propaganda that the protestors were foreign agents acting against Iran’s revolutionary Islamism. The Green Movement sought to portray Montazeri as the modern-day equivalent of Hussein, whose martyrdom at the hands of oppressive rulers Ashura commemorated and used the occasion of his funeral to revive demonstrations. Montazeri’s death placed the regime between a rock and a hard place, as it could not ban processions for the revered figure outright despite his fierce criticisms of Khamenei. Despite a heavy security presence, hundreds of thousands of mourners staged what turned into the largest opposition rally in months, daring Khamenei and his security services to mimic the role of the oppressive Umayyad Caliph Yazid. During the pre-revolutionary period, Ayatollah Khomeini had painted the Shah as the inheritor of Yazid’s legacy, but now, the Green Movement cast Khamenei in the same light. While sensitive to the potency of such symbolism, Khamenei’s forces ultimately opted to crack down against Montazeri’s mourners with batons, tear gas, and pepper spray.

Ahead of Ashura, Khamenei was determined to finally break the Green Movement’s back. Iranian authorities canceled all leave for security and emergency personnel and placed hospitals on alert for massive casualties in anticipation of intensified violent clashes. Demonstrators braved the ominous signs and staged massive protests nationwide, with the largest protests concentrated in Tehran. With protestors increasingly directing their ire at Khamenei, the day’s violence reached its apex as they seized a police kiosk in Vali Asr Square, prompting the police to drive a car through the crowd of protestors. Multiple deaths, scores of injuries, and thousands of arrests were reported around Iran that day. The violent crackdown on the 2009 Ashura protests further eroded Khamenei’s political and religious legitimacy, as it was unprecedented and taboo for his purportedly clerical regime to unleash violence against the citizenry on a holy day.

The Green Movement sought to use the February 2010 day of commemoration of the Islamic Revolution as the next opportunity to challenge the regime. However, by this time, Khamenei and his security forces pulled out all the stops ahead of the holiday to ensure the movement’s failure. The regime shut down internet servers and mobile networks ahead of the day, blocking opposition activists and organizers from being able to coordinate, and throngs of pro-regime loyalists and basijis were bussed into key public squares in a massive show of force. As a result, the movement’s leaders called off their planned protests, effectively marking the end of the Green Movement’s phase of street-level activism. The Green Movement entered a period of soul-searching as it considered new tactics and strategies to channel popular discontent with Khamenei and the regime. However, the movement had ultimately been defeated. A year later, in February 2011, with the Arab Spring protests roiling the region and stoking fears in authoritarian governments, regime security forces placed Mousavi and Karroubi under house arrest, where they remain to the present day, after calling for solidarity with the demonstrations for democracy.

Khamenei’s ultimate suppression of the Green Movement in the aftermath of the fraudulent 2009 election consolidated power further in his hands but came at great cost as it marked a fundamental transformation of the Islamic Republic. The regime could no longer credibly claim to derive any authority from the consent of the governed, and its claims to legitimacy through divine right were challenged further by its deviation from Islamic law and morality in violently repressing the protests. The regime’s response to the protests divided the clergy, although few clerics dared publicly speak out as Khamenei controlled the vital purse-strings. As a result, the clergy’s reliance on Khamenei increased, but the largest shift was that both Khamenei and the clergy became completely dependent on the IRGC to maintain and enforce their control. Iran was effectively transformed into a praetorian state, a military-led dictatorship with a clerical façade. While the system increasingly relied on the IRGC for survival, Khamenei retained singular authority as the primary decision-maker. An uneasy leadership triangle emerged among the Supreme Leader, IRGC, and clergy that became increasingly insular and hardline over the ensuing years to ensure its continued survival.