Yes this is a direct threat of using nuclear weapons, but addressed for the NATO. This becomes clear if seen in the context of the speech. The cold war has act

Yes this is a direct threat of using nuclear weapons, but addressed for the NATO. This becomes clear if seen in the context of the speech. The cold war has actually never ended and the situation is getting worse. My argument is that this is not the premise of the article: "people worry about whether Putin could turn to tactical nukes if faced with a total defeat in Ukraine." Putin has enough conventional weapons for not to use the tactical weapons in the Hiroshima/Nagasaki desperate style.