I see Mohamed Heikal has just died full of years and honour. He wrote a book from the Egyptian side in the preparations for the 1973 war. In it he told a story that I have never forgotten.

I haven’t the book any more so I have to tell the story as I remember it.

The time was the early 1970s and the Israeli Air Force was really busting up the Egyptian defences along the Canal – Israel had conquered up to the eastern edge in 1967. Nasser and Heikal went to Moscow to get help from the Soviets.

So they’re in the meeting room and Brezhnev and Kosygin are on the other side of the table. We need new air defence weapons, says Nasser. OK, say B&K, no problem. Ah, says Nasser, but there’s another problem we need your help on. While our people are training on the new weapons, we’ll need somebody to man the existing defences. So we want you to send us troops to run the existing air defence systems and fly the planes. No way! say B&K, that’s too much. Never! Oh dear, says Nasser, I guess I’ll just have to go home, tell the Egyptian people that I’ve failed and that we’ll have to go to Washington for protection. B&K confer, and agree to sent troops.

What’s the lesson? It is that great powers – and most international affairs pundits – think the great powers always control their clients. But they’re wrong: as this story shows, the clients frequently manipulate the great powers.

The reason is that for the great powers it’s a sideshow, for the clients it’s the only show; for Moscow this was one of many balls to keep in the air, for Cairo it was the only ball. Cairo had much more to gain from understanding how Moscow worked and where the hot buttons were than Moscow had in understanding Cairo. And, in this case, Cairo’s investment of time and study paid off.

Just because, for example, Ankara is a “client” of Washington, doesn’t mean that Ankara always follows the script written in Washington. And we certainly know that Israel and Saudi Arabia have invested a great deal of effort and money to influence, if not altogether create, the script that Washington reads from in the Middle East.

The tail often wags the dog; maybe even more often than not.

Heikal’s Lesson I call it, and I’ve never forgotten it.