We woke up this morning wondering whether the million-person demonstrations that the protest leaders had called for today would materialize.
The first thing I ran into on my way to the Square was something I hadn't seen before. A small crowd of about 150 people demonstrating for Mubarak in front of the Foreign Ministry on the Nile River.
The atmosphere was much different from Liberation Square. Here, people were clearly terrified.
These were the regime supporters afraid of losing everything: the president they've known for 30 years, afraid of the chaos they feared their country would fall into.
I was jostled and pinned to the wall. So urgent was their fear and their need to tell me how much they loved Mubarak, they got so close I could feel their breath on my face.
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Just a few hundred yards away, at the next bridge over the Nile, protesters were beginning to stream into Liberation Square. This was about 10 a.m. Cairenes are notorious for staying up well into the night and getting a late jump on the day. These days, staying out late into the night means ignoring the government imposed curfew -- and they are doing it.
When we got to the outskirts of the square we found the military lining the protesters up, letting them in after checking IDs. They were being helped by the protesters themselves who had organized into volunteer groups to assist with the security. Just as in airports around the world, women were in one line, men in another.
I asked the person checking me what she was looking for. She said "bombs, knives."
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Once inside the square we were astonished once again to find that this is more like a block party than an angry demonstration. People holding signs, people who wanted to talk, to tell us their hopes and their dreams.
After all these days, I finally asked one of the protesters -- who like so many speaks beautiful English -- "didn't Mubarak do anything good for you?"
I was moved to hear this man say, "Yes, he did. He saved our country and did good things for many, many years. But he stayed too long and became obsessed with power. That is his tragic story."
And then, like young people all over the world, he said to me, "This is about our honor and our dignity."
As the day wore on and the television cameras overhead showed the biggest crowds we've seen in a whole week of protests, it was impossible for us to count how many were there. But every time we turned around the protesters wanted us to tell people outside of Egypt that they numbered "1 million, 2 million, even 5 million." All this because they were angry with their own state television which they said had been broadcasting that they were only 20,000.
As darkness fell, groups were singing songs and vendors were selling colorful balloons -- a sign of celebration here in Egypt.
This feels like momentum building to a critical point. It feels, even, like a tipping point. But I don't know how it's going to end.
And, of course, the looming question here is: If Mubarak leaves, what comes next?
I asked many people today: "But who are your leaders?"
People were confused about that.
Many people came up to me and asked if I had any inside information to share with them about what the end of this story would look like.