I don't think much of the much-hyped threat of Russian "little green men"--Russian special forces without national insignia pretending to be indigenous forces--to NATO
states.
Those Russian special forces that are viewed with such alarm since Crimea relied on complete chaos and lack
of organized Ukrainian resistance in Crimea in 2014. And the little green men failed in the Donbas
against even a minimally mobilized Ukrainian force, requiring direct
intervention by Russian army units to achieve a partial conquest and
stalemate there. They simply aren't a general threat against a cohesive state.
And you know what I think of that subliminal "hybrid war," anyway.
What I think is more of a threat to NATO would be a Russian brigade
stripped of national identification and pretending to be a rebel force pulling a Kargil War scenario and occupying Narva, Estonia, and daring NATO to counter-attack to kick them out.