I was once in San Francisco, and I parked in the only available space, which happened to be on the other side of the street. The law descended on me. Was I aware of how dangerous the manoeuvre I’d just made was? I looked at the law a bit blankly. What had I done wrong? I had, said the law, parked against the flow of traffic. Puzzled, I looked up and down the street. What traffic? I asked. The traffic that would be there, said the law, if there was any traffic. This was a bit metaphysical, even for me, so I explained, a bit lamely, that in England we just park wherever we can find a parking space available, and weren’t that fussy about which side of the street it was on. He looked at me aghast, as if I was lucky to have got out of a country of such wild and crazy car parkers alive, and promptly gave me a ticket. Clearly he would rather have deported me before my subversive ideas brought chaos and anarchy to streets that normally had to cope with nothing more alarming than a few simple assault rifles. Which, as we know, in the States are perfectly legal, and without which they would be overrun by herds of deer, overbearing government officers, and lawless British tea importers.