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Yesterday Kenya defied expectations. Voting in a referendum on a new constitution was peaceful, and yet the changes this piece of paper could make are potentially momentous. It would introduce an impeachable president, MPs recallable by their constituents, a land commission to look at historic injustices, an expanded bill of rights, a reformed judiciary. These are causes for which generations of opposition leaders have fought. It took a fraud-plagued election in 2007, in which Kenya teetered on the edge of civil war, to put this on the agenda, as a requirement of the peace deal. But, if the opinion polls are correct, it will happen. It is not a magic wand, but – as Maina Kiai, a former chairman of the Kenya national commission on human rights, said – it is a...