Deterrence, and twisting the arm of NATO. For the war to end, Ukraine needs to believe that Russia won't just turn around and try again in a few years. Realisti

Deterrence, and twisting the arm of NATO. For the war to end, Ukraine needs to believe that Russia won't just turn around and try again in a few years. Realistically, that either means being part of NATO (i.e. that NATO has formally committed to let them join once a peace of some form is agreed) or nukes. They'd rather be part of NATO, nukes are a crappy second option, but they know NATO doesn't like nuclear proliferation, so they will threaten to develop their own nukes if NATO doesn't commit to letting them in.