North Africa has been convulsing for weeks. First, Tunis and now Cairo and Alexandria. For both a familiar script: massive street demonstrations by the young and jobless and desperate and angry, met up against by overwhelming state violence, tear gas, curfews. (Above: an Egyptian demonstrator kisses a riot policeman, now a widely-circulated photo.) The public service that Al Jazeera is providing really is incredible, as reflected in my feed from repostings by @lisang (Lisa Goldman) and @jeremyscahill (Jeremy Scahill). And of course @dailydish (the ever-present Andrew Sullivan).

To digest, the authorities in Cairo, who have been receiving American diplomatic and financial largess since the late 1970s, have now cut off internet access and closed the airport. Hosni Mubarak is trying to put out a fire that does not appear to be quenchable. Meanwhile in Israel, which has been used as another vital US client, there was a peaceful assembly of 20,000 citizens against its government for its perilous decisions but nothing at all like the sturm und drang surrounding it, particularly at its northern border where Hezbollah now holds the reins of power in Beirut.

No one has a crystal ball with which to divine how all of this turns out across the region, the implications for US policy, etc. But it is needless to say how momentous it all is, and that before we can figure out all of the details many things will be totally changed. If that is too general a statement it is of course intended to be, since events are moving too quickly.