Existential threats

A recent Russian press conference:

https://lite.cnn.com/en/article/h_112c4d58f0a10422771f84ae165caad5

First of all, they tacitly admit that they haven't achieved *any* of their goals.

But they also say they will nuke anybody they consider an "existential threat."

I am reminded of my classical history course.  Rome (as in, the Roman Empire) saw itself as peaceful, and had a strict code for engaging in a "just war."  It had to be done properly.  The thing is, over time the way Rome perceived an "existential threat" evolved from "anyone who is actually attacking us" to "anyone who has declared war on us" to "anyone who is preparing to march to war against us" to "anyone who might, in the future, *think* about attacking us, so we'd better attack them first."