Katie Miller, the wife of President Trump's deputy chief of staff Stephen Miller, posted an image of Greenland covered by the U.S. flag on X.

Analysts say the Cold War agreement allows the president to increase the American military presence almost at will.

Trump has recently doubled down on his argument that the U.S. needs Greenland to ensure its own security in the face of supposed rising threats from China and Russia in the Arctic.

Still, coincidentally, the last foreign territory purchased by the United States was from Denmark. It bought the Virgin Islands in 1917 for $25 million. A few subsequent U.S. territorial expansions in the South Pacific were the result of annexations and treaties, according to the Global Policy Forum, a watchdog.

President Donald Trump has repeatedly said he wants to take Greenland, which has received extra weight after the capture of Maduro in Venezuela. Why?

Canadian leaders reportedly plan Greenland visit in February amid growing international tensions over President Donald Trump's annexation comments.

Trump has said the U.S. needs Greenland as a matter of national security and has criticized Denmark’s defenses on the island. Denmark has countered that the U.S. already has a m

Secretary of State Marco Rubio told lawmakers during a classified briefing on Capitol Hill earlier this week that the U.S. is seeking to purchase Greenland, sources familiar with the matter confirmed to ABC News.