Like politician’s careers, journeys often end in disappointment and sadness. Fortunately, that usually gets forgotten as the memory lays down a rich seam of summits and highlights, powered by the copious photographs taken at those moments. My notebooks do a similar thing: page after page of intensely scribbled notes when the going is good, blank pages at the end, rarely a single mention of the flight home, apart from the time when the plane was diverted in a terrifying typhoon and we were grounded for a week in Taiwan. I wouldn’t have minded, but the flight was from London to Manchester.