Thank heaven, though, one of the few mistakes I haven't made is to talk about the unwritten book.

Treason is very much a matter of habit, Smiley decided.

Agents of disruption, subversion, sabotage and disinformation tunnelers and smugglers, listeners and forgers, trainers and recruiters and talent spotters and couriers and watchers and seducers, assassins and balloonists, lip readers and disguise artists.

The trouble is, when professional spies go out of their way to make a definitive statement about one of their own, the public tends to believe the opposite: which puts us all back where we started.

I think that most of my books are part of some process of self-education, often about the places I go to. Most of all, they are about the peculiar tension between institutional loyalty and loyalty to oneself; the mystery of patriotism, for a Brit of my age and generation, where it runs, how it should be defined, what it's worth and what a corrupting force it can be when misapplied. All that stuff is just in me and it comes out in the characters. I don't mean to preach, but I know I do, and I'm a very flawed person. It's quite ridiculous.

For all the flailing and huffing and puffing, there is a kind of fatality about the process of war-making and the excuses we find for it, the consolation of belligerence in politics.

When you're my age, you have the feeling sometimes that you're seeing the show come round again.