Medvedev said NATO and other defense leaders should think about the risks of their policy…Former Russian President Dmitry Medvedev, an ally of Kremlin chief Vladimir Putin, warned the North Atlantic Treaty Organization (NATO) on Thursday that the defeat of Russia in Ukraine could trigger a nuclear war…”The defeat of a nuclear power in a conventional war may trigger a nuclear war,” Medvedev, who serves as deputy chairman of Putin’s powerful security council, said in a post on Telegram..