In Egypt, April 25 is Sinai Liberation Day, a holiday marking Israel’s 1982 withdrawal from the territory, which it occupied after the 1967 war. Usually, this day is a source of national celebration, but this year it was marred by tension, with security forces on high alert and citizens warned against participating in demonstrations.

The source of regime concern proceeded from what had been expected to be both a high-profile and successful five-day visit to Egypt earlier this month by Saudi King Salman. However, during the visit, the Saudi monarch and Egyptian President Abdel Fatah al-Sissi signed not only economic agreements but also a provision to “return” Tiran and Sanafir, two islands at the mouth of the Red Sea’s Gulf of Aqaba, to Saudi control. In Egypt, the opposition was immediate, vocal and, perhaps most importantly, high-profile. Social media and traditional media alike were full of outrage at this territorial concession.

The agreements – worth about $25 billion – come at a time of widespread economic dissatisfaction in Egypt. Indeed, scholars and other analysts agree that the country is fast approaching economic collapse. The Egyptian pound (LE), long pegged to the dollar, traded at 7.83 LE to a dollar in February. A month later, when allowed to float briefly to offset the black market value, the currency immediately dropped to 8.95 LE/dollar. Another devaluation may soon be necessary, since its black market value continues to drop.

With each devaluation, prices of everyday goods rise and dissent grows. Salaries of the small middle class — not to mention the tens of millions trapped in poverty — cover fewer and fewer daily needs. The pension system for the bloated 6.5 million-strong state sector is increasingly meaningless as prices rise and the LE drops.

Meanwhile, tourism on the Red Sea beaches has declined since the bombing of a Russian jet in October, and the Nile Valley tourism that focuses on pharaonic Egypt has yet to recover from the 2011 uprisings. Even the military, with its vaunted economic empire, has become just the most recent subsidizer of the Egyptian state rather than profiting from it.

Part of the regime’s formula for distracting the citizenry — the flip side to the growing repression that has characterized the period since the ouster of President Mohamed Morsi in July 2013 — has been mega-projects, initiatives intended to appeal to popular patriotism and enhance national pride. Among grand plans Sissi has announced are the construction of a new capital and a million new housing units. The companies of “Military Inc.” widened the Suez Canal at breakneck speed, at a cost of $8 billion. However, most of these projects seem likely to remain either on the drawing board or, as in the case of the highly touted Suez Canal extension, fall far short of the promised revenue projections.

The literature on the rentier state has examined the complex relationship between economic crises and the prospects of instability or reform in rent-dependent authoritarian states. However, as the late Samer Soliman demonstrated in his book “Autumn of Dictatorship,” the Egyptian regime, when on the brink of economic disaster in 1990, managed to avoid significant reform and remain in power thanks to significant debt forgiveness received for participating in international military coalitions against Saddam Hussein. Now, Sissi seems to be banking, literally, on a combination of aid and investment from the United Arab Emirates, Kuwait and Saudi Arabia to keep Egypt’s economy afloat.

Until now, the post-July 2013 Egyptian military-security regime had been largely successful in repressing dissent, whether through its brutal assault against members, both real and imagined, of the now-outlawed Muslim Brotherhood, or through harassment, arrests and worse of laborers, civil society activists and human rights workers. Using a legitimation strategy that wrapped various policy initiatives in hyper-nationalism and portrayed opponents of any sort as traitors, the regime managed to convince large swaths of the population that it was the only force powerful and patriotic enough to defend the country against the remnants of the Brotherhood or the even bloodier insurgents in Sinai claiming affiliation with the Islamic State militant group, also known as ISIS, ISIL and Daesh.

However, Sissi and his advisers failed to appreciate the implications or logical outcome of a legitimation strategy so completely grounded in nationalism when they announced the return of Tiran and Sanafir. The history of the control and sovereignty over the islands is complex, evidenced by the flurry of justifications and stinging critiques that followed. But for the vast majority of average Egyptians, these islands are part of the national territory. School instructors were reportedly flummoxed by the announcement that what they had been teaching from government-approved textbooks for decades was suddenly incorrect and were uncertain how to respond to their students’ questions.

None of this would matter much if the islands had remained solely a source of “academic” controversy. They did not. While popular dissatisfaction is very important, the fact that this opposition was quickly and widely promoted by what had previously been a slavishly sycophantic Egyptian media suggests that a red line has been crossed. With many top political commentators taking the president to task for this agreement, opposition has been legitimized for the first time, opening greater space for dissent by those emboldened by the effective defection from regime ranks of some of its most stalwart supporters.

Why is this case of the islands so provocative? Quite simply, there is nothing more central to the civic identity and national narrative than the borders and geography of the national territory.

The literature on national narrative construction across regions has shown that significant changes in the official story — whether interpretation of historical events, national mission or societal values — are likely to occur only during periods of crisis — political, economic or socio-cultural. However, the research also shows that even in such circumstances, there are limits to which elements in the narrative may be modified (and how) short of a major change in regime.

What happens most often is a kind of re-scripting — a reinterpretation of national symbols or key events, a redefinition of existing orientations to allow for policy innovation. In other words, leaders, political elites and regimes may make concessions on less tangible forms of sovereignty, such as national economic decisions in the form of structural adjustment agreements. Ceding national territorial sovereignty, absent conditions of extreme duress is extremely rare, however — and potentially dangerous.

Such a move is particularly problematic in the Egyptian case. Since the overthrow of the monarchy in 1952, successive governments have made Egyptian control of its national territory a central part of the country’s story and mission. This emphasis on  sovereignty over national territory was one of then-President Gamal Abdel Nasser’s justifications for nationalizing the Suez Canal Co. in July 1956. Then, after the devastating June 1967 war, while Egyptians reeled under the impact of the defeat, Nasser’s driving policy message was to “erase the remnants of the aggression,” meaning restoring Egyptian sovereignty over the Sinai, which Israel occupied as a result of the war. In the same vein, Anwar Sadat sold his controversial peace treaty with Israel in 1979 on the grounds that it would result in Israeli withdrawal from Egyptian territory, a promise that was finally completed on April 25, 1982.

As a result, Sissi — who has repeatedly likened himself to Nasser — cannot both promote a nationalism that has deep roots in the identity cultivated over decades among Egyptians through a range of educational, governmental and media sources and violate one of the most basic pillars of that same patriotic national identity with impunity. Some of the slogans in the numerous protests that have taken place since the announcement of this agreement make clear these bases of the popular rejection of the agreement: “Land is honor” (al-ard ‘ard) and a variation on the January 2011 classic “Bread, freedom, social justice” to (the equally rhyming in Arabic) “Bread, freedom, these islands are Egyptian.”

When Egyptians revolted on Jan. 25, 2011, they chose the Hosni Mubarak-designated National Police Day to launch their protests. Ironically, the issue of the islands, just off the coast of the Sinai Peninsula, is at the core of Sinai Liberation Day protest demands. This is not to suggest that a national insurrection will follow today’s demonstrations — extensive preemptive security measures prevented large, mass gatherings — and there is no question that the deteriorating economy is the greatest challenge to the subsistence of millions of Egyptians. But this episode does underscore how potent the central elements of a national narrative can be in challenging a leadership, opening otherwise closed space for expressing opposition to a repressive regime.

Laurie A. Brand is the Robert Grandford Wright Professor of International Relations and Middle East Studies at the University of Southern California and author most recently of “Official Stories: The Politics of National Narratives in Egypt and Algeria,” (Stanford University Press, 2014). Joshua Stacher is an associate professor of political science at Kent State University and author of “Adaptable Autocrats: Regime Power in Egypt and Syria,” (Stanford University Press, 2012).