Verbose
Deity
Trump doesn't. And should Trump actually pursue this – it's a gift to Putin.With the US officially considering expansion to non-US territories, that de facto means it no longer recognize the principle of inviolability of borders which governed international law since world war 2.
And before some guy believing he's smarter than he is tells me that this principle never applied, it must be well-understood first. What it is saying isn't that a subdivision from a larger sovereign state cannot become independent from that state. It also doesn't say that a country cannot military intervene in a foreign one to overturn its governement. It says that a country cannot expand to a foreign territory without the consent of that territory. That is because Saddam Hussein violated that principle when he invaded Kuwait that he faced an international coalition against him. Also, when Russia invaded Crimea, and later the whole South East of Ukraine, that is the reason why he organized pseudo-referendums to justify the "consent" of invaded territories.
Also, should the US somehow make off with Greenland, quite possibly Russia will take Svalbard in retaliation, which then involves the Norwegians.
Trump has to decide if he, and his USA, really is the enemy of Europe? Musk is, we already know.
If Greenland is the bridge here, and Trump might go for it – considering Greenlanders have expressed interest in the idea of greater cooperation with Canada (not the US, way too exploitative in its predilictions), maybe the EU should look into a package-deal for both Greenland and Canada – as a counter-weight to Trump's US? Trump has been talking smack about Canada as well.
In the end. Europe needs it's own defense architecture independent of the US, and possibly against also the US, which might or might not include Greenland. But if so, it would be simplified if it then also included Canada. It is about future competition over the Arctic region. Denmark and Norway the intention might be to just push out, legality or no, Russia is already positioning itself. And even Canada might go on Trump's chopping block – unless there is actual push-back and alternatives.
The Arctic Council has kind of imploded already after Russia going rouge in Ukraine. If the US also goes rouge as well, there's nothing left. Or possibly a wind-up for Trump's style of transactional politics that would instead reward Putin's Russia.