President Hosni Mubarak's counter-revolution smashed into his opponents yesterday in a barrage of stones, cudgels, iron bars and clubs, an all-day battle in the very centre of the capital he claims to rule.
It was vicious and ruthless, and bloody and well planned, a final vindication of all Mubarak's critics and a shameful indictment of the Obamas and Clintons who failed to denounce this faithful ally of America and Israel.
The fighting around me in the square called Tahrir was so terrible that we could smell the blood. The men and women who are demanding the end of Mubarak's 30-year dictatorship -- and I saw young women in scarves and long skirts on their knees, breaking up the paving stones as rocks fell around them -- fought back with an immense courage that later turned into a kind of terrible cruelty.
Abuse by both sides had provoked a shower of rocks from Mubarak's men -- yes, they did start it -- before the protesters who seized the square began to hurl them back.
By the time I reached the 'front' line -- which moved back and forth over half a mile -- both sides were screaming and lunging at each other, blood streaming down their faces.
"This is Mubarak's work," a wounded stone thrower said to me. "He has managed to turn Egyptian against Egyptian for just nine more months of power. He is mad. Are you in the West mad, too?"
Only when I had passed the radio building did I see the thousands of Mubarak-supporting young men pouring in from the suburbs of Cairo. There were women, too, mostly in traditional black dress and white-and-black scarves, a few children among them.
They told me they had as much right to Tahrir Square as the protesters and they intended to express their love of their president in the place where he had been so desecrated.
And they had a point, I suppose. The democrats -- or 'resistance', depending on your point of view -- drove out security police thugs from this very square on Friday. The Mubarak men included some of the very same thugs I saw then, when they were working with armed security police to baton and assault the demonstrators.
In Cairo, I walked beside Mubarak's ranks and reached the front as they charged into Tahrir Square. The sky was filled with rocks, six inches in diameter, which hit the ground like mortar shells. On this side of the 'line', they were coming from Mubarak's opponents. They cracked and split apart and spat against the walls. I hared towards safe ground where the stones no longer hissed and splintered, and suddenly I was among Mubarak's opponents.
An increasing number of men among the anti-Mubarak protesters wore Islamist dress -- short trousers, grey cloaks, long beards, white head caps. They shouted 'Allahu Akbar' the loudest and bellowed their love of God. Yes, Mubarak had done it. He had brought the Salafists out against him, alongside his political enemies. From time to time, young men were grabbed, their faces fist-pulped, screaming and fearful of their lives, documentation found on their clothes to prove they worked for Mubarak's interior ministry.
And where, amid all this hatred and bloodshed, was the West? Sometime around 3am yesterday, I had watched Lord Blair of Isfahan as he struggled to explain to CNN the need to "partner the process of change" in the Middle East.
We had to avoid the "anarchy" of the "most extreme elements". And -- my favourite, this -- Lord Blair spoke of "a government that is not elected according to the system of democracy that we would espouse". Well, we all know which old man's "democracy" he was referring to.
Street rumour had it that Mubarak might actually creep out of Egypt on Friday. I'm not so sure. Nor do I really know who won the Battle of Tahrir Square yesterday, though it will not remain long unresolved. At dusk, the stones were still cracking on to the roads, and on to the people.
After a while, I started ducking at passing birds.