If Putin/ Russia become seriously threatened as a nation and the generals decide to send off a single nuke to demonstrate they are serious in defending their country, guess where they will send it?
They will nuke Pine Gap, a tactical target for "5 eyes" communication. They will do this because;
Minimal impact on human civilisations/ homes
It won't devastate Europe, sending them into war
It will send a clear message to the US that the next one heads that way, without the Pentagon doing a massive over-reaction counter attack a mainland US strike would trigger.
Russia knows full well our fair weather allies, the UK and USA, will not do shit. Just look how they treat one of our own, Assange.
Are you not glad we are part of the white English speaking privilege club? You'all feel safer under AUKUS? I don't.