What a contrast between Tienanmen Square 1989 and Tahrir Square 2011! It was the army that made the difference. Deng Xiaoping had loyal units that were willing to roll tanks over demonstrators, Mubarak and his Vice President had only their police and a few horses and camels.
What a pity that history is no longer properly taught in the West! Nobody seems to recall Colonel Urabi's Revolution of 1881-82, which was ended by a British invasion to re-establish colonial rule. Nor do people speak of Saad Zaghloul's Revolution of 1919, which led to the British abandoning its protectorate and allowing free elections, which were won by the Wafd Party. There followed nearly twenty years of parliamentary democracy, but the monarchy that Britain had put in place led to a regime of nepotism and corruption, ended by Colonel Nasser's popular coup in 1952. Nasser was at heart a Westernizer, and his inspiration was the British Welfare State. But his pan-Arab nationalism was unacceptable to Israel, and he never recovered from defeat in the 1967 war.
So Egyptians have been periodically in revolt for 130 years against Western attempts to control their country. The big question is whether this time they will succeed. Already America has demanded that the peace treaty with Israel be respected, although Israel has long since ignored its terms. Nasser's successor, Anwar el-Sadate was assassinated in 1981, essentially because he had betrayed the Palestinians by leaving their interests out of account. Will Egypt now lift the Siege of Gaza? Will it now continue 'normal' relations with Israel despite the continuing colonization of the West Bank and East Jerusalem? Those are important things to watch.