The USA would not have amounted to much if we had not acquired all those territories to the west, north and south.  Maybe President Donald Trump's manifest destiny for Greenland, Panama Canal and Canada might well be visionary.  Make American Even Greater! Original size of U.S. in 1789 = 864,746 square miles. We then grew to 3,531,905 square miles through territorial acquisitions. 1803 Louisiana Purchase from France, 828,000 ( almost the same size as originally ) square miles (sm) for $15 million, now worth $389 billion. 1818, British Cession, 45,417 sm. 1819, Florida, $5 million, Spain, 72,101 sm. 1845, Texas cession, 389,166 sm. 1846, Oregon territory, UK, by contested occupation, 286,541. 1848, Mexican Cession from Mexico, $15 million, 529,189. 1853, Gadsdend Purchase from Mexico, $10 million, 29,670. 1857-1858, Islands in the Pacific, 16 sm. 1867, Alaska, $7.2 million from Russia, 591,000. 1967-1947, islands mostly in the Pacific, like Hawaii, small sums, about 120,0...