It may be that the only real route to peace would be for the Russian governing elite somehow to force Putin out of power. The videos that their leader has released showing him humiliating members of the security establishment, as he compels them to endorse his policies, are meant to demonstrate his total authority. But they also highlight misgivings within his own inner circle.

However, the current Russian system is less collective than even the post-Stalin Soviet Union. High-ranking Soviet officials were able to force Nikita Khrushchev from power in 1964. But Putin rules more like a pre-Soviet tsar. It is hard to see how internal opposition to him, within the government, can mobilise.

It is possible, however, that as the human and economic costs of the war mount it will become more difficult to contain the public protests against the conflict. Russian troops within Ukraine may also become demoralised as they take losses and are ordered to use brutal tactics against civilians. Eventually some combination of elite anxiety, military failure and popular discontent could force the Russian leader out of office. But — for now — the danger that Putin poses to Ukraine, Russia and the world is only growing.