Donald Trump’s campaign to bring Greenland under United States control has often been dismissed as bluster. That is a mistake. Behind the language of a property deal lies a serious attempt to revive an old imperial principle: that Washington may decide the political and economic...

On 14 January, a few hours before the historic meeting in Washington between representatives from Greenland and Denmark and their U.S. counterparts, J. D. Vance and Marco Rubio, Denmark and several of its NATO allies reinforced their military presence in Greenland and announced that more...