Liz is the NATO detterent, I completely forgot about her one useful role: playing the madman nuclear strategy with Putin.NATO would have a problem responding to a tactical nuke. Difficult to be optimistic in the UK ATM, knowing Liz has our nuclear button in her handbag. She's not known for discussing her next move in Cabinet.
That she has a need to destroy the UK economy and public services is your internal problem, mate.
You respond to a tactical nuke by a similarly destructive demonstration. You can't let it slide. And you give the button to the Ukrainians and repaint the missiles because technically you are not at war with Russia.