Moreover, the military chiefs have shown dexterity and flexibility and have reached out to the young leaders of the pro-democracy revolution. Exploratory talks have begun between the two camps, an important signal that the generals are serious about political engagement with the new leaders of politicized young Egyptians.

Although the opposition and protesters welcomed the communiqu├ęs by the Supreme Council of the Armed Forces, led by Field Marshal Mohammed Tantawi, they have rightly demanded the release of political prisoners, the lifting of a state of emergency, the abolition of military courts, fair elections and a swift handover to civilian rule.

Egypt's generals have said they will ultimately lift emergency law, used to stifle dissent under Mubarak, but they have not specified a timetable. They have also refused to release political prisoners.

For the moment, the generals, particularly Tantawi, a close ally of Mubarak, are in full control. So are many senior ministers. So are the small parasite-business community allied with the Mubarak regime whose vested interests count for so much in Cairo. It is no wonder then that many Egyptians are anxious about the old guard hijacking of the revolution. There is a real danger that change could be aborted by the old marriage between the parasite business community and the power-security elite.

Egyptians must keep their eyes on the big prize: Mubarak's departure, seismic though it is, was never the final goal of this uprising. The real aim is not the removal of one tinpot dictator, only for him to be replaced with an equally repressive system. The real goal is something much more fundamental: the removal of a corrupt and parasitic power structure and its replacement with transparent, open government and the rule of law. Simply put, the goal is to replace the authoritarian and closed power structure with an open society and polity.

This is a historic opportunity to transform Egypt to a full-fledged democracy. But now is the time, not tomorrow. This is the moment, and it is a brief one. If it is not seized, the loss will be momentous. The way the transition is managed will determine the political and economic structure in the post-Mubarak Egypt. Although internal negotiations will be decisive, the US role is also important given the extent of American financial assistance to the Egyptian army and frequent contacts since the revolution erupted on 25 January.

In the Philippines, in Indonesia, across Eastern Europe, wherever lasting change was achieved, it was achieved because democratic voices made themselves heard at once. If that does not happen right away the danger is that Egypt will go back to business as usual. There is an urgent need to agree on a specific road map for democratic transformation and consolidation.

So the critical question is "How do we give voice to the millions of newly politicized Egyptians?" They have no affiliation but they are determined to be heard. Unless they are organized, a task that requires time, effort and resources (all in short supply), their voice will fade away. They must immediately raise the critical questions for the future of their country. Who will be in charge of building newly open institutions? And can the military chiefs possibly sacrifice their economic interests to more pluralistic, install democratic values - or will they fight to the end to preserve the status quo under different disguises?

Those are troubling matters. Still, for all the dangers, no one should underestimate how powerful a moment this is. The departure of Mubarak marks the beginning of the fall of the authoritarian wall in the Arab world. Mubarak was the public face of political authoritarianism in the region: he has built one of the most feared security forces in the world numbering almost 1.5 million. His exit proves the power of the people. It removes the barrier of fear in the region. The events since 25 January have created a sense of empowerment that has swept Arab societies on every level. From Algeria to Iran, a non-Arab country, the ripple effect of the Egyptian revolution is shaking Middle Eastern dictators to their foundation.

In Egypt itself the victory has been sudden and only the night before it seemed a long way away. The old guard has been trying hard to find ways of keeping Mubarak in power. The Army and the Americans, perhaps, made the difference. It was the army statement after Mubarak's last defiant speech that made it clear they were telling the dictator "It's not working any more." And yet they have fought tooth-and-nail to keep the system in place, to keep the reforms incremental, to sustain the system under which they have risen so high.

Those efforts tell you just how removed from reality they are, how delusional, how clueless. Until the very last moment, I don't believe Mubarak had any intention of leaving: he and Omar Suleiman simply did not understand the gravity of this crisis. Instead, they treated a cancer as migraine.

But in the power structures that have been left behind, some vestiges of the sickness remain. Egypt will not truly be cured until the entirety of the old regime is gone.

Fawaz A. Gerges is the director of the Middle East Centre at the London School of Economics, London University. He is author of the forthcoming book, "Obama and the Middle East: Continuity and Change."