Austria is an odd example, given that it's completely surrounded by "friendlies". What would the Austrians gain by joining NATO? It's fairly clear what they would lose, which is the ability to stay out of a future NATO conflict.
Thought experiment: let's imagine the UK or the US were to somehow kick off a hot war with - let's say - Chinese forces, on/around the Spratly Islands in the South China Sea.
Do any of us seriously believe that the UK or the US just press some magic "Article 5" button and troops from all over NATO just grab their weapons and set off round the world to join in the fighting?
Looking back at the history of NATO's Article 5 it's clear it has more holes than a Swiss cheese. It's political theatre.[0]
> Austria is an odd example, given that it's completely surrounded by "friendlies".
This kind of thinking has produced the current nightmare IMO. The unwillingness to invest in common security has enabled Russia.
Without wishing to get all silly, most wars tend to involve both sides fighting.
What's the actual threshold for a NATO member declaring "an attack" to be able to claim assistance under Article 5? Their first ship sunk? Their first aircraft shot down? Their first casualty on the battlefield? First civilian killed in terrorist attack? First cyber-attack?
“A serious cyberattack could trigger Article 5, where an attack against one ally is treated as an attack against all” Jens Stoltenberg, NATO Secretary General[0]
It would appear to be a completely blank cheque for military action, based on suitable political theatre. Think Wag the Dog (1997 movie).[1]
[0] https://www.nato.int/cps/en/natohq/news_168435.htm?selectedL... [1] https://en.wikipedia.org/wiki/Wag_the_Dog