The massive victory of the Islamist parties in the Egyptian general elections received its official imprimatur last weekend, and the country appeared headed for a major constitutional tussle between the ruling Supreme Military Council and the emergent parliament.

Egypt announced that, after three bouts at the polls and a number of individual run-off elections, the main 498-member lower house of parliament, the People's Assembly, which convened this week, will have 235 representatives of the Muslim Brotherhood and 121 from the Salafist al-Nour party and its affiliates. Together they will hold 71 percent of the seats—47.18 percent for the Brotherhood and 24.29 percent for al-Nour). The house will contain another ten "moderate" Islamists from the New Center Party. The centrist and traditional al-Wafd Party will have thirty-six members, and the liberal bloc will have thirty-three seats. The "Revolution Continues" party, representing the leaders of the Facebook and Tweeter generation that featured so prominently in the demonstrations that ultimately toppled the old regime, won only 2 percent of the vote.

Given the nature of the gradual democratic takeover of the state by the Muslim Brothers, many observers see the victory of Hamas‚ the Palestinian offshoot of the Brotherhood, in the 2006 Palestinian general elections as the true herald of the revolutionary change in the Egyptian polity (and perhaps of the so-called Arab Spring in general, given its evident Islamist trajectory).

Fresh mass demonstrations are scheduled this week in Cairo's Tahrir Square, marking the one-year anniversary of the demonstrations that overthrew the regime of Hosni Mubarak, who ruled Egypt since 1981. The demonstrators likely will press the army to relinquish its hold on power and subordinate itself to the popular will, meaning accept parliamentary oversight and control of its budget and operations. But many liberal Egyptians suspect that the Brotherhood and the army have already secretly struck a power-sharing deal that will sideline both the secularist liberals and the al-Nour Salafists. If so, the protests will be symbolic and pro forma and will pass quietly.

At the end of this week, Egypt will hold its first elections for parliament's upper house, the Shura Council. After these are completed, the two houses are scheduled to set up a committee to formulate the country's new constitution. The military, headed by General Tantawi, will likely seek to retain its independence from civilian control and possibly its actual control of the state. Elections for the presidency are scheduled for June. The Brotherhood months ago announced that it will not field a candidate from the party ranks—but, given its electoral success, there can be little doubt that it will either eventually put forward a candidate of its own or advance the cause of a straw man of its choosing.

Observers expect the Muslim Brotherhood, which is likely to form a coalition government with the small centrist-secular parties rather than with its Islamist competitors from al-Nour, to focus in the coming months and years on sorting out Egypt's internal problems—consolidating its hold on power, battling the flight of foreign investors, reducing unemployment, shoring up crumbling infrastructure and reviving foreign tourism. Thus, it probably will forego its traditional foreign-policy agenda of breaking with the West and annulling the 1979 peace treaty with Israel. The Egyptian economy can ill afford the loss of the annual American foreign-aid subsidy of $1.5 billion.

But events may confound expectations, as often happens in the Middle East. The core elements of the Brotherhood ideology—anti-Westernism, anti-Semitism, sharia fundamentalism—may come to the fore despite the wishes of (at least ostensibly) more pragmatic leaders. Earlier this month, the spiritual leader of the movement, Muhammad Badia, defined the resurrection of a "world-embracing Islamic caliphate" as the "goal" of the Brotherhood. This must be done in stages, he wrote: First, the individual person must be reformed, "then the family must be built, then the society and the state, and [then] the just caliphate that will guide the world."

In recent weeks, other Brotherhood spokesmen, such as deputy leader Rashad Bayumi, have repeatedly declared that the Israeli-Egyptian peace treaty will have to be reviewed by "the people," implying the eventual holding of a referendum. The treaty was signed, on the Egyptian side, as Bayumi put it, "far from the eyes of the people and parliament," meaning by the unrepresentative, undemocratic Sadat regime. Bayumi also declared that the movement would "never recognize Israel, under any circumstances. [Israel] is a conquering entity." He was referring not to the semi-occupied West Bank, largely populated by Palestinian Arabs, but to the state of Israel itself, which in Islamist discourse is said to be situated on and occupying Arab-Muslim land. Bayumi's statement, in an interview in the Arabic language daily Al Khayat, contradicted assurances given to Washington by other Brotherhood spokesmen that it would not harm Egyptian-Israeli relations.

External factors could also upend the Brotherhood's intention to focus on Egypt's internal problems. Palestinian militants have recently renewed their low-key rocketing of Israel from the Hamas-controlled Gaza Strip, which may lead to a new bout of major Israeli-Palestinian violence. A Brotherhood-led Egypt may find it difficult to stay aloof from such a conflict. And above all looms the Iranian nuclear crisis, which may yet lead to an Israeli-Iranian confrontation. At Iran's bidding, that would probably suck in Hezbollah of Lebanon and Hamas of Gaza. In such an event, the newly configured Egypt wouldn’t likely stay on the sidelines.

Benny Morris is a professor of history in the Middle East Studies Department of Ben-Gurion University of the Negev. He is the author of 1948, A History of the First Arab-Israeli War (Yale University Press, 2008).