Dictators sometimes come to power on a wave of public support for a leader who promises to end civic chaos, but ends up throttling democracy. That may prove to be the case with Egypt's new president, Adbel Fatta al-Sisi, who certainly fits the profile of a strong man unlikely to tolerate dissent.

But following his inauguration last week, Mr. al-Sisi promised to "correct the mistakes of the past," pledging improvements in the economic life of the nation and its people.

Certainly, he would counter expectations by encouraging legitimate differences of view and making room for them to be expressed at the ballot box in future elections. Given Egypt's diversity, that may be the only alternative to a repression that will encourage further turmoil.

As chief of staff of the Egyptian army Gen. al-Sisi led the 2013 military takeover that ousted the elected but hugely unpopular President Mohammed Morsi. The interim government he installed put Mr. Morsi on trial and outlawed his Muslim Brotherhood movement. Mr. al-Sisi seized on the popularity of his takeover to resign from the army and run for president himself.

In last month's election Mr. al-Sisi won an overwhelming 95 percent support. But he failed to obtain the 75 percent turnout he himself sought as a measure of his legitimacy.

Even so, Mr. al-Sisi received almost 24 million votes, while Mr. Morsi, in 2012, got only 13 million. That was the result of a wave of new registration among Egyptian voters. In May there were 54 million registered voters, while in 2012 there were half as many.

That would appear to indicate that democratic sentiment among Egyptians is strong, a factor that President al-Sisi will have to take into account when governing. The government encouraged voter turnout with free bus and train rides to the polls, a one day extension of the three-day voting period and by threatening fines for those who stayed home.

The new president's rule will not be easy. He must restore civil order and crack down on fanatical attacks on Coptic Christians and on the growing al-Qaida presence in the Sinai. His test of strength with the now-outlawed Muslim Brotherhood, which remains strong in many poor communities, promises more turmoil. He needs foreign economic support that will come with strings attached, requiring economic reforms that are likely to generate strong opposition from vested interests, including the military.

Egyptians empowered by the success of street protests in ending the rule of long-time dictator Hosni Mubarak in 2011 and of elected President Morsi in 2013, will be quick to let the new president know of their dissatisfaction.

If he is wise, President al-Sisi will use democratic methods to restore a civil society and allow for the democratic election of a successor. Otherwise, the Egyptians will have elected themselves a new Pharaoh, bringing new troubles.