In January 2005, Mahmoud Abbas, then 70, had just launched his campaign for Palestinian Authority president. Arriving on a grey, mild day in the occupied West Bank city of Jenin, he was lifted on to the shoulders of an ecstatic crowd numbering about 10,000 people. While nowhere near as charismatic as his predecessor, Yasser Arafat, who had died two months before, Abbas was nonetheless welcomed as a reformer and a man of peace. Abbas, commonly referred to by his kunya, Abu Mazen, won the presidency by a significant majority a few weeks later. A major architect of the Oslo peace...