If Putin wants no NATO then all he has to do is get his poodle, Trump, to invade Greenland ...
"If they invade Greenland, they invade Nato," says Svane. "So that's where it stops. Article 5 would have to be triggered. And if a Nato country invades Nato then there's no Nato."
"He's saying it's legitimate for us to take this piece of land," he says. "If we take him really seriously this is a bad omen for the whole of the Western alliance."
It really wouldn't be the end of NATO. Greece and Turkey have had numerous spats while both NATO countries. An Article 5 resolution can be vetoed by any other NATO member. The US would assuredly do this.
A much more worrying possibility would be Denmark specifically withdrawing from or reducing cooperation with NATO. Forget Greenland, Denmark itself is in a very strategic location, considering its place in the Baltic.