‘That’s good,’ said Blackstone. ‘Because I think we’re living through something similar. The 1920s and ’30s, Kate. They were an historical discontinuity, by which I mean the orderly progression of history was shattered. By the slaughter of the Great War. It destroyed empires, re-fashioned the world, swept away an old order and for three decades, and arguably for more, there was no sense of continuity. You change a few decisions here or there, and you change what comes afterwards forever. There was no reason we had to win in 1945. No reason why it had to be the Soviets who lost in 1989 either. It seems inevitable looking back, what the commies used to call “the correlation of forces”, but it was really just one day after another, one decision here, an action taken or not taken there. FDR dying of polio. The Depression running much deeper for longer. Nixon not getting caught and poisoning the well for ever after.’

The Governor looked as though he was enjoying himself with his free-ranging lecture, right up until the point when Musso interrupted him.

‘Are we going somewhere today, Professor?’

A hint of annoyance crossed his face but he composed himself. ‘Ever the literalist, eh Musso?’ he sighed. ‘A common failing of the Jarhead. A lack of imagination and a refusal to learn from history. My service commenced all the way back in Vietnam and you know what I learned there, Kate?’

‘No, sir.’

‘The United States Marine Corps was the finest implement ever crafted for getting young American lads killed for no good reason at all.’

She felt Musso radiate waves of hostility and sensed the tension that suddenly strained at every muscle in his body. Blackstone, meanwhile, seemed to be enjoying himself again, grinning like a cat in front of a big bowl of cream.

‘I learned lessons in Vietnam, Kate. But I learned even more later, including the most important – which was to never stop learning, to never stop questioning your basic assumptions. Colin Powell, God rest his soul wherever it may have been taken, used to be fond of lecturing us about the lessons of Vietnam and the limits of power. But he never questioned himself about whether those limits had changed in the years between our ignoble defeat in Vietnam – for that is what it was, and the revisionists be damned – and the moment of half-achieved victory he engineered in the First Gulf War. If he had asked himself that question, I don’t believe we would have been sitting in the desert in 2003, waiting to finish the job, when the Wave swept everything away.’

‘I don’t recall you being in the desert in ’03, Governor,’ said Musso, as though he was actually racking his memory. ‘Weren’t you in . . . Fort Lewis? Yes, that’s right. I seem to recall something about a military junta you were trying to impose there.’