Having surprised not merely the Obama Administration but apparently members of his own party and the Egyptian military with his defiant decision to stay on on Thursday night, Hosni Mubarak on Friday evening Egyptian time finally gave into 18 days of protests and resigned, handing power to the Army.

This overturned his Thursday evening concession of power to his vice-president Omar Suleiman, who delivered the short, almost tweet-length statement revealing Mubarak’s departure

In the name of Allah the most gracious, the most merciful. My fellow citizens, in the difficult circumstances our country is experiencing, President Muhammad Hosni Mubarak has decided to give up the office of the president of the republic and instructed the supreme council of the armed forces to manage the affairs of the country. May God guide our steps.

After the enormous anti-climax of Thursday evening, when Mubarak provoked fury from the millions of Egyptians now in the streets across the country with a near-delusional speech asserting he would remain in office, Suleiman’s statement prompted wild celebrations among protesters. After 18 days of demonstrations, clashes with security forces, assaults from pro-Mubarak supporters and a sluggish, almost indifferent response from many Western governments, they had achieved their goal of ousting the man whose 30-year dictatorship has exacted a heavy toll in bloodshed, repression and missed economic opportunities.

As Friday’s protests gathered even greater momentum from his non-resignation, Mubarak flew to the Red Sea resort of Sharm el-Sheikh, which as The Guardian nicely pointed out, had on occasion been lent by Mubarak to another discredited American ally, Tony Blair. As it turned out, the dictator was fleeing his capital, one to which he’s unlikely ever to return except, perhaps, as a defendant.

Once the celebrations fade, attention will turn to ensuring that the Egyptian military makes good on its promises made during Friday, when it told protesters it would ensure Mubarak kept his promises of constitutional change, an eventual end to the long-standing state of emergency, and free and fair elections.

The military has taken a stronger role in recent days in detaining, beating and torturing protesters and journalists, casting doubt on its commitment to the sorts of freedoms protesters have repeatedly called for. Nonetheless, as Mohamed El Baradei’s call for intervention by the military yesterday suggested, there were few alternatives for prising Mubarak from office. Omar Suleiman, Egypt’s former spy chief and a known torturer and murderer, was an integral part of the Mubarak regime, one of the reasons both Israel and the United States appeared anxious for Mubarak to position Suleiman as his replacement.

For the moment, however, Egyptians are celebrating a moment many thought would never happen in their lifetimes.