Egyptian President Hosni Mubarak gave into the demands of the protesters today, leaving Cairo and stepping down from power. That came hours after a speech, broadcast live across the world yesterday, in which he refused to do so. Earlier that day, the Supreme Military Council released a statement -- labeled its "first" communiqué -- that stated that the military would ensure a peaceful transition of Mubarak out of office. In practice, it appears that power has passed into the hands of the armed forces. This act was the latest in the military's creep from applauded bystander to steering force in this month's protests in Egypt. Since the protest movement first took shape on January 25, the military has, with infinite patience, extended and deepened its physical control of the area around Tahrir Square (the focal point of the protests) with concrete barriers, large steel plates, and rolls of razor wire. In itself, the military's growing footprint was the next act in a slow-motion coup -- a return of the army from indirect to direct control -- the groundwork for which was laid in 1952.

The West may be worried that the crisis will bring democracy too quickly to Egypt and empower the Muslim Brotherhood. But the real concern is that the regime will only shed its corrupt civilians, leaving its military component as the only player left standing. Indeed, when General Omar Suleiman, the recently appointed vice president to whom Mubarak entrusted presidential powers last night, threatened on February 9 that the Egyptian people must choose between either the current regime or a military coup, he only increased the sense that the country was being held hostage.

The Egyptian political system under Mubarak is the direct descendant of the republic established in the wake of the 1952 military coup that brought Gamal Abdel Nasser and the Free Officers to power. Nasser and the officers abolished Egypt's limited parliamentary monarchy and ousted an entire generation of civilian political and judicial figures from public life. They created their own republic stocked with loyal military figures. Their one experiment with technocratic governance, allowing Egyptian legal experts to write a new basic document, was a failure. The experts' draft had provisions for a strong parliament and limited presidency, which the officers deemed too liberal. They literally threw it into the wastebasket and started over, writing a constitution that placed immense power in the hands of the president.

Such an arrangement would prove to work out well for the military, as every Egyptian president since 1953 has been an army officer. For two generations, the military was able, through the president, to funnel most of the country's resources toward national security, arming for a series of ultimately disastrous wars with Israel. These defeats, combined with the government's neglect of the economy, nearly drove the country to bankruptcy. Popular revolt erupted between 1975 and 1977 over the government's economic policies. To regain control, the military turned its attention away from war and toward development. It gradually withdrew from direct control over politics, ceding power to domestic security forces and the other powerful backer of Egypt's ruling party -- small groups of civilian businessmen who benefited from their privileged access to government sales and purchases to expand their own fortunes.

In the 1990s, Mubarak waged a domestic war against Islamists, and the role of the military evolved further. As the government became dependent on an expanded domestic police force, the army was reduced in size and importance. Over time, the police and the Ministry of the Interior supplanted the armed forces and Ministry of Defense as the keystone of the regime. Meanwhile, the factions of the business elite that fed on the state, such as the now disgraced steel magnate and former ruling party leader Ahmed Ezz, grew more powerful. Mubarak gave them privileged access to the ruling National Democratic Party, which they convinced to open the Egyptian economy to world trade -- enriching them even further.

The officer corps was appeased to some degree, however, by its own economic good fortune. Throughout the 1990s, the army expanded its involvement in the economy. By this decade, industries owned by the military were estimated to control 5 to 20 percent of the entire Egyptian economy; likewise, army officers receive a variety of benefits, such as special preference in access to goods and services.

Today, the army presents itself as a force of order and a neutral arbiter between contending opponents, but it has significant interests of its own to defend, and it is not, in fact, neutral. The basic structure of the Egyptian state as it now exists has benefited the military. The practical demands of the protesters seem fairly simple: end the state of emergency, hold new elections, and grant the freedom to form parties without state interference. But these demands would amount to opening up the political space to everyone across Egypt's social and political structure. That would involve constitutional and statutory changes, such as reforming Egypt as a parliamentary rather than a presidential system, in which a freely elected majority selects the prime minister (who is now appointed by the president). These changes would wipe away the power structure the army created in 1952 and has backed since.

A freely elected parliament and a reconstituted government would weaken the role of the presidency, a position the military is likely to try to keep in its portfolio. Moreover, open elections could hand the new business elites power in parliament, where they could work to limit the role of the army in the economy. This would put the army's vast economic holdings -- from the ubiquitous propane cylinders that provide all Egyptian homes with cooking gas to clothing, food, and hotels -- in jeopardy. Moreover, the army has always preferred that the country be orderly and hierarchical. It is uncomfortable with the growing participatory festival on the streets, and even if the officers were to tolerate more contestation than their grandfathers did in the 1950s, they would likely try to limit participation in politics to those whose lives have been spent in the military by retaining the system of presidential appointment for government ministers.

Indeed, instead of pursuing institutional change, leading military figures will likely try to satisfy the public with symbolic gestures. They would surely investigate the most corrupt businessmen and their ministerial associates for the misuse of public funds and public property. At the same time, there will likely be an investigation of the former minister of interiorfor deliberately murdering demonstrators during the crisis.

If the military takes further control, two of the players currently on the scene will be crucial. First, Suleiman, who has strong ties to the military, is at the center of every negotiation among the opposition factions and is almost constantly on television. Unsurprisingly, he has made it clear that he has no intention of reforming the presidential system. Playing for time, he has consistently insisted that even negotiations should be strictly limited to changing the three articles of the constitution that deal with elections.

Second, although Egypt's defense minister, Field Marshal Hussein Tantawi, has been much less visible, he is no less important. He is behind the army's announcement that it would not, unlike the hated security police, fire on Egyptians. In fact, the army fired on neither the demonstrators nor on the thugs who attacked them, and even went so far as to announce that the protesters had legitimate demands. I have heard accounts of the army arresting some protesters and members of human rights groups. Some of those who have been arrested and released report that a faction of army officers remain sympathetic to Mubarak's appeals that he has a mission to carry out. Still, under Tantawi, the army will likely try to at least appear neutral while negotiating with the rest of the opposition to manage a transition, even as Suleiman works to ensure that reform is limited.

The Mubarak regime as it has existed for the last decade -- an increasingly corrupt and incompetent government that has conferred immense economic advantages on a handful of politically connected businessmen -- has been shattered. A more open political system and a responsive government that ensures its own safety by trimming back the power and privileges of the military could still emerge. And the army may step in as a transitional power and recognize that, as much as it might like to, it cannot return to complete control. The Egyptian military is far more professional and educated than it was in the 1950s, so many officers may recognize the benefits of a democracy. More likely, however, is the culmination of the slow-motion coup and the return of the somewhat austere military authoritarianism of decades past.

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