Editor’s Note: This article originally appeared on Order from Chaos.

Protests erupted in more than 100 Iranian cities over the weekend, sparked by the government’s decision to triple gasoline prices in a bid to fill a budget deficit. Demonstrators blocked traffic on major highways, burned posters of Iranian leaders in effigy, and attacked banks, government buildings, and symbols of the revolutionary system. The regime responded immediately and with brute force, imposing a near-total blackout of the internet and mobile lines and deploying snipers and security forces to the streets of its own cities. Iran’s supreme leader, Ayatollah Ali Khamenei, denounced the demonstrators as “thugs” and its president, Hassan Rouhani, warned that government surveillance would empower reprisals against all who participated. If the unofficial reports of dead and wounded are anywhere near accurate, this might be the most deadly uprising since the 1979 revolution.

The demonstrations echo the unrest that convulsed Iran in late 2017 and early 2018, although this latest round appears to be more widespread and more violent. The Trump administration’s “maximum pressure” strategy has surely contributed to Tehran’s fiscal predicament. However, Iran’s turmoil is not driven by U.S. policies, nor is it merely some circumstantial spasm. The protests are the latest salvo in the Iranian struggle for accountable government that stretches back more than a century. And the fury and desperation of the Iranians on the streets this week strikes at the heart of the legitimacy of the revolutionary system.

A Long Familiarity with Protest

Despite its well-entrenched mechanisms of repression, the Islamic Republic has experienced a vigorous pattern of mostly small-scale unrest since its inception, a legacy of the revolution itself as well as the old Persian tradition of bast, or seeking sanctuary as a form of political protest. After the monarchy was ousted, collective action—both spontaneous and opportunistic—was a primary mechanism for gaining advantage in the chaotic struggle for power.

Most infamously, this led to a student-led seizure of the American embassy in Tehran 40 years ago this month, an action that toppled Iran’s liberal-leaning provisional government and permanently escalated tensions between Washington and Tehran. Iranians’ penchant for protest has continued, as has its cynical deployment by the regime itself, whose internal schisms have frequently occasioned official and semi-official groups to use public demonstrations to advance their own agendas.

As a result, Iranians are well familiar with political, social, and economic protest. Over the course of the past 40 years, Iran has routinely witnessed all varieties of rallies and riots; sit-ins by families of political prisoners; labor strikes by teachers, truckers, and factory workers; student demonstrations over everything from free speech to dormitory conditions and cafeteria food; soccer riots; and marches and sit-ins sparked by localized grievances. These manifestations have never been limited by geography or class.

Endurance of the Nezam

Rarely have these demonstrations threatened the viability of the Islamic Republic, whose security forces have overwhelming capabilities to manage or repress discrete demonstrations. And so far these latest episodes have remained quite modest by historical standards—at least an order of magnitude smaller than the million-plus Iranians who came to the streets in 2009, after the contested reelection of hardline President Mahmoud Ahmadinejad. Even then, the regime managed to rebound.

The durability of the Islamic Republic is perhaps the most important legacy of 1979 revolution. None of the extraordinary developments within or around Iran over the course of the past 40 years has managed to significantly alter it—not the considerable evolution of Iranian society, nor the country’s steady reengagement with the world, nor the incremental reforms advanced by various factions within the establishment. In many respects, the structure of power in the Islamic Republic seems even more firmly embedded today than it was at any point since its precarious creation.

The staying power of Iran’s post-revolutionary system lends itself to a certain fatalism; if war, internal upheaval, regional turmoil, natural disasters, crippling economic sanctions, and near-constant infighting among the political establishment have failed to weaken theocratic authority, perhaps any hope for change is simply futile. Not long ago, this perception prompted some younger Iranians to disengage from politics. A reporter who interviewed young Iranians in 2005 found “an overwhelming picture of a generation lost, disaffected and stained by longing.”

What Has Changed

Nearly 15 years later, however, Iran’s “lost generation” is now approaching the age of the revolution itself, and the absence of a promising political or economic horizon has become painfully acute—and not simply for elites, but for the larger population of Iran’s post-revolutionary youth. These Iranians have benefited from the revolution’s dramatic expansion of educational opportunities and broader social welfare infrastructure. That legacy and the regime’s populist promises have shaped their expectations for a better life and sense of political entitlement to a functioning, responsive government.

The 2015 nuclear deal only supersized those aspirations. Tehran’s narrative around the agreement stoked expectations of monumental economic opportunities and perhaps even more than that. “This will bring hope to our life,” an Iranian man commented in the midst of the jubilant celebrations that greeted the deal’s conclusion. “Now we will be able to live normally like the rest of the world,” another remarked. It was not to be. Even before Washington withdrew from the nuclear agreement in May 2018 and began reimposing sanctions, Iranian frustrations with the slow pace of the deal’s peace dividend fed a broader sense of disenchantment—not simply with an individual policy, official, or institution, but rather with the entire political establishment and the ruling system. After 40 years, Iran’s political zeitgeist has moved from revolution to reform to repudiation.

Those frustrations began to manifest in a higher pace and intensity of instability. The Iran Human Rights Documentation Center recorded more than 1,200 labor actions related to non-payment of wages between January 2017 and November 2018. The apex came in the final days of 2017 and early 2018, when what apparently began as a provincial political stunt quickly flared into a spasm of furious demonstrations. Within 48 hours, protests were convulsing in at least 80 cities, and the refrains of the demonstrators had catapulted from economic grievances to explicit denunciations of the system and the entirety of its leadership.

That episode, like the current one, highlights the dangers posed by the pervasive frustration and alienation. It is clear from Tehran’s reaction to the latest eruption of protests that the leadership is unnerved, and for good reasons: the rapid progression from mundane, localized demands to radical rejection of the system as a whole; the transmission and coordination of protests via social media rather than mediated through the more manageable traditional press; the engagement of the government’s core constituency, the rising middle class; and the near-instantaneous dispersion from local to national. These factors expose the profound vulnerability of the Islamic Republic at a time when U.S. sanctions are severely limiting resources that might enable Tehran to address or preempt the sources of dissatisfaction.

What Next?

Economic grievances have served as the backdrop for each of Iran’s prior periods of political ferment during the past century. In each of Iran’s most significant turning points over the past 150 years—the Tobacco Revolt, the Constitutional Revolution, the oil nationalization crisis, the 1979 revolution—financial pressures intensified and expedited the political challenge to the status quo.

Tehran today is facing an epic, interconnected set of crises: the crisis of unmet expectations, which feeds a crisis of legitimacy for a system whose waning ideological legitimacy has been supplanted by reliance on a more prosaic emphasis on state performance and living standards. Iran’s predicament is exacerbated by the uncertainties surrounding leadership succession, both with respect to the position of the supreme leader, who marked his 80th birthday earlier this year, and the legions of senior officials from the same generation who helped shape the post-revolutionary state from its inception.

To overcome its internal liabilities, the Islamic Republic can rely a time-tested playbook of repression and cooptation. But each collision between a furious citizenry and an inflexible structure of power leaves fissures in the system. Eventually, as happened 40 years ago in Iran, even the most well-fortified regime will shatter.