Currently, as NATO members, they are not likely to be attacked, but if NATO declares war then that deterrent is gone.
Hopefully not a likely scenario, but who knows.. There's been a lot of tension lately, especially with the likes of Belarus bussing migrants across the border into Lithuania etc, but no idea where this will end.
"Article 5 provides that if a NATO Ally is the victim of an armed attack, each and every other member of the Alliance will consider this act of violence as an armed attack against all members and will take the actions it deems necessary to assist the Ally attacked."
So, the 9/11 attacks were considered an armed attack on the United States, and the alliance deemed it necessary to overthrow the Taliban in order to prevent Al-Qaeda from perpetrating similar attacks again.
One can disagree with the rationale behind the decision, or the cost-benefit ratio. But it did follow the protocols of the alliance.
... is a very different thing than ...
> occupying a foreign country for 20 years
When NATO invaded the towers were still smoking, the war-on-terror intelligence apparatus had yet to be built, and we (I) had no idea whether another attack was forthcoming. It felt pretty damn reasonable at the time.
This is the deterrent—and it also rhymes with the Triple Entente v. Triple Alliance tensions that set off the Great War.
Are they really?
> So while the use of armed force is one way to respond to aggression, the NATO has several options, for example:
> Nothing. They might decide that the best way to "restore and maintain security" is to just let the attacker have that country.
Germany aid to Ukraine was to send them 5k helmets.
Those helmets didn't do anything against Russia's missiles.
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That is, attacking a member of NATO just means that all other members must help it, but how they help, is up to them, and that help can be just a pat in the back.
In the end, there is no supranational tribunal for military allegiances - in matters of conflict, Hobbes' jungle is still very much there.
The US is not obligated to intervene in Ukraine, plain and simple. The US has a strategic partnership with Ukraine, I think, but it's not an ally. https://www.defense.gov/News/Feature-Stories/Story/Article/1... https://www.state.gov/u-s-ukraine-charter-on-strategic-partn...