Editor's note: Shadi Hamid is director of research at the Brookings Doha Center and a fellow at the Saban Center for Middle East Policy at the Brookings Institution. You can follow him on Twitter: @shadihamid
(CNN) -- After the first competitive elections in Egypt's history, many Egyptians find themselves straddling the divide between the deposed regime of Hosni Mubarak and its 84-year-old Islamist adversary, the Muslim Brotherhood. Polarization has long been a problem for Egypt. Now there is more of it than ever.
The two candidates who received the most votes will face off in the second round in mid-June. The Brotherhood's candidate, Mohamed Morsi, is trying to get liberals and leftists to hold their noses and vote for him. Ahmed Shafiq, the last prime minister of the old regime, promises to save Egypt from the "dark forces" of Islamism. He is a largely unreformed autocrat who cites Mubarak as a "role model" and says the "strongest thing should be the state."
The fault lines that run through Egyptian politics are ones that often appear during democratic transitions. In Eastern Europe after the fall of communism, for example, there was widespread concern over the so-called "Red Return" -- the election of former communists to power. In most cases, the old autocrats distanced themselves from past abuses and repackaged themselves as newly believing democrats.
In Egypt, however, many members of the old regime, like Shafiq, remain unrepentant. He was prime minister while protesters were being killed during Egypt's revolution, and now may become its first post-revolution president. This very real possibility raises the question: Should politicians of the old regime be allowed to return to government and serve in senior government posts in the new Egypt?
As Yale University's Ellen Lust argues, "Retaining space for local elites helps to ensure that they buy into democracy instead of trying to subvert it." But what if these elites use the democratic process to subvert it from within?
In Tunisia, by contrast, the transitional government banned elites of the old ruling party from running in elections. A Shafiq victory, if it comes to pass, may prompt other transitional countries to carefully consider how to use legal channels to block an electoral "restoration" of the old order.
A second fault line in Egypt is between majoritarianism and consensus-driven politics. Many liberals believe that the Muslim Brotherhood betrayed the spirit of the revolution by trying to assert full control over the country's elected institutions. Most controversial was the formation of the constituent assembly, which was dominated by the Brotherhood as well as ultraconservative Salafis. Liberals responded by withdrawing from the assembly.
The presidential election results have provoked a similar debate, with liberals calling on Mohammed Morsi to commit to sharing power with the two runner-up candidates by appointing them as co-presidents or vice-presidents with considerable powers. Others have called on the Brotherhood to appoint a technocratic government with a non-Islamist prime minister.
The Brotherhood, meanwhile, believes in a distinctly majoritarian form of democracy. It won 47% of seats in the lower house of parliament and more than 50% in the upper house, the Shura Council. Where liberals argue that one party should not dominate both the parliament and the presidency, the Brotherhood, in the run-up to elections, argued the opposite: Because the legislative branch remained relatively weak, the group needed the presidency to fulfill the promises it made to the electorate.
Here, the Brotherhood speaks of its own "Turkish model." In Turkey, the thinking goes, the Islamically oriented Justice and Development Party succeeded in turning the country around because it had full control of both branches of government.
On the day of the election, a Morsi campaign aide told me that the "unity of the legislative and executive branches" would lead to greater stability in Egypt. Having different parties in control of different branches, on the other hand, would only lead to continued polarization. Interestingly, he cited Britain and Israel as examples of majoritarian democracy. Of course, Britain is an established democracy and Egypt is not. It took Turkey's embattled Islamists decades to get where they are today. The Brotherhood, fearing military intervention and a return to repression, is apparently less patient.
In the coming days, the Brotherhood and the liberal-leftist opposition will have a small window of opportunity to reconcile their competing visions of the transition -- a transition that is now being called into question. If they fail, they might all find themselves on the same side, just as before, facing a president and powerful military that will, once again, have managed to divide and conquer.
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The opinions expressed in this commentary are solely those of Shadi Hamid.