Millions of Egyptian protesters have erupted in anger against the ruling Muslim Brotherhood and President Mohammed Morsi. Millions took to the streets across the country on Sunday, the anniversary of Morsi's inauguration, and threatened widespread civil disobedience if he doesn't step down by Tuesday evening. Young protesters stormed and ransacked the Brotherhood's Cairo headquarters, which they see as the true seat of power.

Will Morsi be able to restore calm and hang on? The embattled president — vilified by the opposition for ramming through an Islamist-inspired constitution and failing to fix the crumbling economy — admitted he had made mistakes, but said he wasn't going anywhere. "If we changed someone in office who [was elected] according to constitutional legitimacy — well, there will be people opposing the new president too, and a week or a month later they will ask him to step down," he told Britain's Guardian newspaper.

Crowds like these got rid of the authoritarian regime of Hosni Mubarak, and plenty of people are starting to predict that Morsi is doomed to a similar fate, even though he was duly elected. John Hinderaker at Power Line suggests that the Obama administration might soon regret having "put America’s thumb on the scale on the side of the Brotherhood."

The course Egypt is on is unsustainable, as its economy is close to utter collapse. I don't see how the current Muslim Brotherhood regime can stave off that collapse, so change of some sort seems inevitable. Perhaps it will be for the better. [Power Line]

One crucial question is whether the protesters can maintain this level of energy long enough to get results. Rick Moran at American Thinker says the Muslim Brotherhood appears to be confident that it can either wait out the protests or muster enough supporters to prevail. "Past protests since Mubarak fell have petered out after a few days," he notes, "so we'll have to see how this one unfolds."

These protests, however, aren't like previous ones. They are bigger, and more powerful. At least seven people died in clashes since the crowds — which the military has estimated at 14 million, although not everyone believes it — took to the streets on Sunday. Jeremy Bowen at BBC News says all sides were surprised by the scale of these demonstrations, which were supported by everyone "from supporters of the old Mubarak regime to people who risked their lives to topple it." The government could be in trouble, he suggests, if it can't do something to drain their momentum.

President Morsi's spokesman has called for dialogue. For that to work, the president would have to offer major concessions, perhaps on a rewritten constitution. He showed no signs of conciliation during a major political speech last week, instead appealing to his Muslim Brotherhood base. [BBC News]

In the end, it might not be the Muslim Brotherhood or the demonstrators who decide Egypt's fate. Mike Giglio at The Daily Beast points out that it was the army that "ran Egypt between the 2011 downfall of former dictator Hosni Mubarak and Morsi's inauguration as Egypt's first democratically elected president a year ago." The generals, who faced allegations of abuse, appear reluctant to get back into politics, he says, but if the risk of chaos becomes too great, they might step forward and say whether Morsi stays or goes.

In an ominous sign, Egypt's military chiefs called the protests an "unprecedented" sign of the public's will, and on Monday gave Morsi's government 48 hours to come up with an "inclusive road map" out of the crisis. Stay tuned.