In the winter of 1939-40 the German Marxist critic Walter Benjamin wrote a remarkable text known as “Theses on the Philosophy of History”. In it he attacked the widespread belief on the left that socialism would come about inevitably, as the fruit of historical progress. “Nothing has corrupted the German working class so much as the notion it was moving with the current,” he wrote. Revolution is not the appointed result of humankind’s “progression through a homogeneous empty time”. Rather, “it is a tiger’s leap into the past,” which mobilises the memories of past suffering and oppression against the ruling class. And Benjamin concluded by evoking the fact that, in the Jewish Messianic tradition, “every second of time was the strait gate through which the Messiah might enter”. 1 Revolution, in other words, is not a predictable outcome of a forward historical movement—it is a sudden, unexpected irruption into a history that is a “single catastrophe which keeps piling wreckage upon wreckage”.2 Benjamin wrote these words at a very dark historical moment, “midnight in the century”, when the Hitler-Stalin pact seemed to symbolise the death of all radical hope. But they fit the revolutions that have swept through the Arab world since mid-December like a glove. Exploding apparently out of nowhere, quite unanticipated, an explosion of resentments deeply compacted over decades, they are not simply rewriting the political map of the Middle East, but have a much broader historical meaning.