Charles went home after a breakfast of toast and marmalade, but with no butter—I really needed to go to my local supermarket.

‘Shall I leave you the shotgun and cartridges?’ he asked as he was packing his other stuff into his car.

‘We would both be breaking the law if you did,’ I replied. Maybe we had done so already, as the weapon in question had been in my charge all night anyway, but at least he’d been in the same building.

‘So, is that a yes or a no?’

‘Yes,’ I said. ‘But only if you are happy about it.’

‘I’m not happy about it one bit. But I’d be a lot less happy if your house got burned down with you in it.’

Charles was nothing if not pragmatic.

‘I promise not to fire it unless it’s necessary.’

‘I should hope not.’

‘And, even if I do,’ I said, ‘I’ll not actually shoot at anyone. It’ll just be a deterrent.’

‘But deterrents don’t work if you’re not prepared to use them. Do you remember the Falklands War back in 1982? Who would have thought that Argentina could have been so stupid as to attack Britain, a nuclear power—but they did. But even then, we didn’t use our modern and very expensive nuclear arsenal—of course we didn’t—and the Argies knew all along that we wouldn’t, so it had no deterrent effect whatsoever.

‘However, a single and almost obsolete Vulcan bomber, flying the 8,000-mile round trip from Ascension Island to the Falklands and back, just to drop a few ineffectual Second World War bombs across the runway at Port Stanley, had far more impact as a deterrent. The Argentine junta believed, quite rightly, that we could, and would, do the same to Buenos Aires, so they kept most of their air force at home to protect their capital city. And that may well have been the difference between us winning and losing that war.’

‘So are you telling me, in a roundabout manner, to use your gun to shoot someone?’

‘Yes, I am, if you have no alternative. If they know for certain that you won’t shoot at them, it’s not worth having the gun in the first place. Indeed, it could be more of a liability than a help, especially if it is captured and then used against you. That’s what happened to the British Army at Rorke’s Drift.’

‘Rorke’s Drift?’

‘During the Anglo-Zulu War in southern Africa. Almost a third of our deaths at Rorke’s Drift were due to the Zulus firing our own rifles back at us—rifles that had been either captured from us earlier, or actually ripped from the hands of the defenders themselves as the battle unfolded.’

‘How on earth do you know that?’ I asked him with incredulity.