Ouch. Just ouch.
Ukraine's response to Moscow deciding to fuck them over in the dead of winter by cutting off gas supplies (the linked article misstates the issue: it's not just a rate hike, it's "eat this rate hike, immediately, or we freeze your poor to death.") by threatening to give the US a radar base in Sevastopol, as well as completely dicking over an important segment of the nuclear arsenal that is Moscow's remaining military clout worth talking about. (And word on the street is that a lot of their domestic nuke arsenal is poorly-maintained to begin with, though that may have changed now that the Kremlin is flush with gas money).
Letting NATO come into Sevastopol has got to be the Russians' worst geopolitical nightmare, as it effectively seals them out of the Black Sea for eternity and would give us a point-blank view on everything happening within Post-Soviet airspace.
No question about it: this week, the gloves have finally come off.