It is always better to leave politics at a time of your own choosing. Very few do, because politics is such an exciting career that most people cannot bear to let go. I had reached the highest office I could aspire to (leader of the Senate), and I had been attorney-general and, before that, the shadow attorney-general, for ten years. In my final year, I led two very important law reforms: marriage equality, and reform of Australia’s national security law relating to foreign interference. So I had a perfect opportunity to go out on a high, and I took it. It wasn’t an easy decision, but it was certainly the right one – much better than the way most political careers finish. There are similarities and differences between my previous jobs and my current one. I am still a public figure, and still closely involved in policy at the highest level. But there are important differences too: I am an observer and an interpreter of events, rather than a protagonist. So there is less adrenaline. It’s...