Nobody can read Vladimir Putin's mind. But I think whatever his goals may have been at the beginning of this war, they have surely changed by now. Even if he had intended to move beyond Ukraine, that is now not on the cards. Mr Putin has his hands full. Ukrainian resistance and the international response have been firmer and more widespread than Mr Putin probably expected.
Moving beyond Ukraine would entail a direct confrontation with The North Atlantic Treaty Organisation and that is simply too dangerous. Mr Putin's announcement of a higher nuclear alert was a signal that he understood this reality and that Europe and the United States should not intervene directly. Nuclear deterrence will keep the peace between Nato and Russia, as it did during the Cold War, and contain the war to Ukraine.