My guess is that Putin moved all the troops in the hope that he could extract some kind of concessions from NATO and Ukraine without going to war. What concessi

My guess is that Putin moved all the troops in the hope that he could extract some kind of concessions from NATO and Ukraine without going to war. What concessions would have satisfied him is unclear. According to one German general something quite small, more symbolic that material, might have been enough: anything that he could present as a victory in the tame Russian media. But NATO and Ukraine offered him nothing at all. Bringing the troops back without having achieved anything would have made him look weak or stupid. So he had to invade. If that's roughtly right, why didn't NATO and Ukraine offer him some small symbolic concessions? Well, I would guess that one reason is that the US administration wants there to be a small war in Europe because then Western Europe will stop buying Russian gas and will have to buy US gas instead. This is obviously something they care about a lot because they've been trying really hard to stop Nord Stream 2, even to the extent of applying sanctions against German companies involved in the project. Also look at the propaganda they've been producing against Nord Stream 2. Almost every issue of The Economist has a few paragraphs claiming that building an additional, alternative pipeline will somehow make Germany "dependent" on Russian gas, as opposed to just giving them another option. Anyway, it's a mess, but I hope they hold back on the sanctions a bit, so that they have some in reserve to apply later, and that people like Macron carry on with the diplomacy.