I wrote a piece published today by Defense One on the nuclear aspects of the ongoing crisis between Russia and Ukraine:

The risk that a Russian invasion of Ukraine by conventional forces could lead to the use of nuclear weapons appears relatively low, but their shadow is never completely absent from a crisis involving nuclear-armed states. Moreover, this crisis—no matter how it ends—seems likely to lead toward more strategic instability, not less. As preoccupied as U.S. diplomats must be with the threat of imminent conventional invasion, they must also work urgently to launch confidence-building measures that might prevent a nuclear war.

The recent back-and-forth between Washington and Moscow has been free of explicit nuclear threats, but there has been some nuclear signaling. As Russia massed forces near Ukraine in December, its foreign ministry released two proposed treaties, one for NATO and one for the United States. The draft of the NATO treaty included an article prohibiting the deployment of missiles previously outlawed by the Intermediate-range Nuclear Forces Treaty. The draft of the U.S. treaty had more explicit references to nuclear weapons, including pledges to not deploy them outside national territory and to not train personnel from non-nuclear countries in their use—a reference to NATO nuclear-sharing arrangements.

The rest of the article can be found on the Defense One website.