When President Trump announced that the United States had reached an agreement with Denmark that would allow the United States to both protect the World’s largest island and control the development of its resources he made history in a big way. In effect Greenland would now be an American protectorate and managed from Washington.
The scale of this achievement can best be understood by comparing the size of President Trump’s acquisition and President Jefferson’s Louisiana Purchase which virtually doubled the size of the United States (United States before purchase: roughly ~890,000 sq. mi.; Louisiana Purchase: ~828,000 sq. mi.; United States afterward: roughly ~1.7 million sq. mi.).
Greenland is 836,000 square miles so it is slightly larger than Jefferson’s Louisiana Purchase. Thus President Trump can now legitimately claim he is the president who added the most territory to American jurisdiction if not ownership.