A question to Americans

I posted this to /r/trump first, but it was only downvoted and not answered so I try it here.

I’m your typical liberal European living in Berlin, Germany, and I have a genuine question for Americans, especially those who support Trump. As you might expect, I disagree with Trump on nearly every issue, but that’s not what this post is about. Policies such as anti-immigration stances or the “national interest first” approach—which, unfortunately, sometimes includes abandoning democracies invaded by authoritarian-imperialist states like Russia—are sadly not unfamiliar to me. These political views also exist in Europe; in Germany, for example, they’re currently stronger than ever, with the AfD reaching 20.6% in our recent national election. However, here’s what puzzles me deeply: Trump’s position on Denmark and Greenland. I honestly cannot imagine that even the most extreme right-wing party in a European democracy would, after coming into power, approach another sovereign, democratic ally and demand, “Sell me your territory, or else…” This kind of stance feels completely detached from any influential European political tradition since 1945. Therefore, I wonder: isn’t this something that would make even the most conservative Americans pause for a moment and think, “Wait a minute, can this really be right?” Is there any notable opposition within Trump’s own camp to his stance on Greenland?