Egyptian flags adorned streets across Egypt, along with banners declaring support for el-Sissi and hailing his latest achievement. Patriotic songs, some written especially for the occasion, blared from TV and radio stations on Thursday, declared a national holiday by the government.
Banks and most businesses were closed and authorities, in sharp contrast to the government's zero tolerance for political demonstrations, allowed people to gather on streets and squares to celebrate the occasion.
The new Suez Canal extension involved digging and dredging along 45 miles (72 kilometers) of the 120-mile canal, making a parallel waterway at its middle that will facilitate two-way traffic. With a depth of 79 feet (24 meters), the canal now allows the simultaneous passage of ships with up to a 66-foot draught.
The project was initially estimated to take three years, but el-Sissi ordered it completed in one, something the pro-government media hailed as evidence of the president's resolve and seriousness.
The government says the project, funded entirely by Egyptians, millions of whom bought canal bonds, will more than double the canal's annual revenue to $13.2 billion by 2023, injecting much-needed foreign currency into an economy that has struggled to recover from the 2011 uprising that toppled President Hosni Mubarak.
Economists and shippers, however, have questioned the value of the project, saying the increased traffic and revenues the government is hoping for would require major growth in global trade, which seems unlikely.
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On Thursday, el-Sissi appeared to acknowledge that the project would not yield an immediate windfall, saying it was also meant to reassure his countrymen and the world that Egyptians "are still capable" of great accomplishments.
The man-made waterway linking the Red Sea to the Mediterranean, which was inaugurated in 1869, has long been a symbol of Egyptian national pride. Pro-government media have compared el-Sissi to former President Gamal Abdel Nasser, a charismatic leader whose nationalization of the canal in 1956 was seen as a defiant break with the country's colonial past.
"Egypt makes history," read the banner headline of Thursday's pro-government daily Al-Watan. "Rejoice, it is worth it!" proclaimed the front page of another daily, Al-Maqal.
Thursday's inauguration came a day after an Islamic State group affiliate calling itself the Sinai Province of the Islamic State released a video threatening to kill 30-year-old Croatian Tomislav Salopek in 48 hours if authorities do not release "Muslim women" held in prison, a reference to female Islamists detained in the government's crackdown on former President Mohammed Morsi's supporters.
El-Sissi made no mention of the kidnapping, but denounced the Islamic militants battling his government as "evil people" seeking to "hurt Egypt and the Egyptians."
"Without a doubt, we will triumph over them," he added.
Egypt has seen a surge in attacks by Islamic militants since Morsi's ouster, in both the restive north of the Sinai Peninsula and the mainland, focusing primarily on security forces.
Militants have also targeted foreign interests, including the Italian Consulate in Cairo, which was hit with a car bomb last month. That came just days after another bomb killed Prosecutor General Hisham Barakat in an upscale Cairo neighborhood.