His hands were jabbing at the air. He was seeing in his head the eleven sites chosen across the country where the American military bases were being constructed, picturing the nuclear arsenal piling up in storage silos on our doorstep. I knew. I’d seen them inside my own head.

‘For heaven’s sake, Isaac, see sense. The Soviet Union has installed Communist governments in all the countries of Eastern Europe and if it thinks it can get away with it, it will invade and crush Western Europe, as it tried to do when it blockaded West Berlin in 1948. The American nuclear threat is all that keeps them from our door.’ I waved a hand towards the huge arched door behind us. ‘Tell that to your friends out there. And remember this: the Soviets have just detonated their own atomic bomb, which means we are in an arms race that—’

‘No, no.’ My brother shook a fierce finger at me. ‘It was not a true H-bomb, not like America’s explosion at Enewetak in the Pacific last year. That one was a monster. A thousand times more powerful than the one dropped on Hiroshima. The Soviet bomb didn’t have a staged fusion device.’

I stared at him. My little brother used to be always skiving off to sail his dinghy on the lagoon instead of doing his maths homework, yet here he was talking about staged fusion devices.

‘How on earth do you know that?’ I asked. ‘About the fusion device.’

‘So you still think that because I didn’t go to university like you and André, I have shit for brains.’

‘No! Of course not.’

‘Just because I work on the waterfront in Marseille and spend my days loading and unloading bloody great ships, doesn’t make me a dumb knucklehead, you know.’

‘I know that, Isaac.’

His voice grew louder and I threw a quick glance around the church. Nothing moved in the shadowy confession box or the gilded pulpit with its carved-eagle lectern. But still I checked out the Our Lady chapel with the blue-draped Madonna stained-glass window and the grand altar space with its candles burning steadily. Even the gilt box in the wall that displayed the service hymn number. We were alone.

‘Wearing a docker’s vest and dungarees,’ Isaac could not let it go, ‘doesn’t mean I can’t read or listen. Yes, I wield a docker’s hook. That doesn’t mean I don’t know what questions to ask. Education of the masses lies at the heart of Stalin’s Communism.’

There we had it.