The Egyptian regime of Hosni Mubarak is attempting to extinguish the large-scale opposition that has taken to the streets this week in unprecedented numbers.
It will have to move fast - much is at stake.
While the popular unrest is unlikely to be able to unseat the President in Tunisian style, it is large enough and potent enough to put the credibility of Mr. Mubarak on the line.
If his veiled threat to unleash deadly force does not keep protesters at bay, and if many more protesters are killed (three died in Suez on Tuesday), Mr. Mubarak may be able to save his regime but at the expense of his good name.
Will the army stand by the President? Mr. Mubarak rose to the presidency through the military (as did his two predecessors). But even after almost 30 years in office, he is not guaranteed its continued support.
Just as the army must ultimately approve of the next choice for President, so too it puts its authority above this regime.
Will the army consider it appropriate to suppress protests with deadly force? Or will it seek a more conciliatory end to the incidents?
But it's not just Mr. Mubarak's credibility on the line, his opponents must also juggle perceptions.
The Muslim Brotherhood, named by the regime as the instigators of this week's protests, had little or nothing to do with the activity in the streets. And that's a problem for them.
As the main opposition voice, they can't afford to let the parade leave without them. How they balance their need to be seen to lead, and yet to avoid being wholly suppressed by force, will test their mettle.
The leaders of this week's protests seem to hail from a number of disparate, mostly secular groups.
In Cairo they represented the more affluent advocates of civil liberties, much like the Tunisian revolutionaries.
But in Suez and in other centres around the country, they came by the thousands from the ranks of the unemployed, or underpaid, who struggle to live.
Can all these interests consolidate? That is the tough task they must face.