Authorities of Panama and Greenland have repeatedly said they won’t hand over any territory to Trump, with Panama’s president declaring that the canal "is going to stay in our hands forever," and Denmark’s prime minister insisting “Greenland is not for sale.”

Few took the president-elect’s combative comments at face value, but they still sent a shudder through a country that has been invaded by the United States before.

President-elect Donald Trump on Tuesday said he would not rule out the use of military force to seize control of the Panama Canal and Greenland, as he declared U.S. control of both to be vital to American national security.