They agree when their interests agree, and they have plenty of treaties and rules between them when it comes to this sort of minutia. The question is, is any of them better served by a rotating Olympics than a fixed one? If the answer is yes. Say, because it gives them a chance to gain soft power via a PR demonstration of hosting the Olympics, then it will clearly not change. But my point is not that it will change, my point is that what the IOC wants doesn't decide that, what the governments involved want does.

One possible way to explain the current situation is that there is a big incentive for both the EU and, in a lesser degree, the US, to have the Olympics fixed in Greece, a country inside the western system of alliances. Conversely, there is a big incentive for China and Russia to be able to compete for hosting the Olympics themselves or have them hosted in states that are more closely aligned with them, even with the economic cost involved. Smaller countries have incentives to both host or avoid hosting the Olympics. But none of this, none, depends on petty corruption from the IOC. This is not an engineering problem, but it is also not a business problem. As you pointed out just now, it is a geopolitics problem.

(Sorry, I'm getting tired; it's well past my bed time here. Only replying to one of your points.)

> There is a big incentive for both the EU and, in a lesser degree, the US, to have the Olympics fixed in Greece,

I think you have misunderstood the current dynamics in the EU. There would be a very, very, very big resistance towards giving Greece a gift like that, after their giant national financial fraud towards the rest of the EU during the past decade.

Well then lets do the Summer Olympics in Greece, and the Winter Olympics in St. Petersburg.