It would be truly hell.
A NATO counter-offensive would be bloody and fraught with escalatory risk—but it’s one of the probable outcomes of a Russian invasion. In that eventuality, Russian conventional forces—of which only a portion are well trained and well equipped—would likely be severely damaged or even destroyed. Moreover, if NATO forces hit targets inside Russia or crossed over into Russian territory, Moscow might conclude that there is a danger to the existence of the state. After all, Moscow has expressed concerns in the past that regime change by the West is an all too real danger. In that situation, Russia might counter advancing NATO forces with its arsenal of tactical nuclear weapons.
While a recent RAND Corporation study concluded that Russia could overrun NATO’s member states Estonia, Latvia and Lithuania in the Baltics within sixty hours, the war games did not simulate the use of nuclear weapons. If, however, a war were to breakout between NATO and Russia, nuclear weapons would certainly come into play—especially if the conflict were going poorly for Moscow.
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