Anthony Shadid writes: If the demonstrations that culminated in February were an uprising against President Hosni Mubarak, the revolt today is against his legacy.

“This is the real revolution,” said Mohammed Aitman, helping at a first-aid clinic in a turbulent, roiling and, at times, ecstatic Tahrir Square.

The vestiges of Mr. Mubarak’s order —the military, the Muslim Brotherhood and other Islamists, or fragmented liberals and leftists — seem ill prepared to navigate the transition from his rule. It is an altogether more difficult reckoning that has echoed in the Arab revolts in Syria, Libya, Yemen and Bahrain.

The strategy that for so long successfully repressed public anger and sapped people’s will to rebel was no longer working. As a result, it is not at all clear what path Egypt will find to go forward. The authorities hoped that the protesters would exhaust themselves and go home, but they have not. The military tried violence, but it has not worked. It has tried limited concessions, but that did not work. And it has blamed foreigners for inciting the violence, and that did not work.

This may foreshadow a dangerous and prolonged period of unrest in Egypt, as the spectacular show of discontent on Tuesday in Tahrir Square demonstrates that there is no existing institution to channel their frustrations.

The military appears largely oblivious to the scale of the protests, and Islamist parties are single-mindedly pursuing their political goals as they predict a healthy showing in the coming elections. No leader, of any ideological bent, has emerged to capture the full array of discontent once again spilling out onto the streets.

“Today, it is a failure of the political class,” said Ibrahim el-Houdaiby, a political analyst at Dar al-Hikma, a research center in Cairo. “People feel betrayed.”