He says it's because we "need" Greenland's minerals. Others in his administration are going along with that, but it's bullshit, and he doesn't really have any idea what he's talking about. Some people have, of course, told him he's wrong, as they've told him his ideas about tariffs are stupid, and didn't even work the way he's been trying to use them in the 19th century.
But in his second term, and doddering old age, he only listens to people who tell him what he wants to hear.
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