Land Purchase is Common

In 1803, President Thomas Jefferson purchased the Louisiana Territory for $15 million from Napoleon.  This purchase included the cities of New Orleans and St. Louis.

In 1819, President James Monroe purchased Florida from Spain.  The Adams-Onis Treaty traded American claims to Texas and $5 million for ownership of East and West Florida.  St. Augustine and Pensacola became American cities though the population was Spanish.

In 1848, President James K Polk sought to purchase California and New Mexico from Mexico.  He offered up to $30 million for the territory.  Any Mexican president who looked like he might negotiate such a deal was deposed.  Santa Anna returned from exile to fight the Americans.  After Mexico decisively lost the war, the US nonetheless paid $15 million for the territory.

In 1854, President Franklin Pierce approved the Gadsden Purchase, which added around 30,000 square miles to Arizona and New Mexico Territories.  This also included the city of Tucson.  Interestingly, Santa Anna was President of Mexico at the time.  At this time, Pierce also offered to buy Cuba, but Spain declined.

In 1867, President Andrew Johnson approved the purchase of Alaska from Russia for $7.2 million.  Viewed as a bad purchase, it was called Seward's Folly.  William Seward was the Secretary of State.  It is noteworthy that Seward also wanted to buy Greenland.

In 1898, President William McKinley purchased the Philippines from Spain for $20 million.  Though the US had defeated the Spanish fleet, it had only captured Manila Harbor.  The payment was to acquire all of the Philippines.

In 1903, President Theodore Roosevelt paid $10 million for the Panama Canal Zone.  Of course, he had helped Panama secede from Columbia when Columbia had refused a treaty for the canal zone.

In 1903, President Theodore Roosevelt began paying rent for Guantanamo Bay on Cuba.  Though the US had long flirted with acquiring Cuba, when it actually was acquired, the Congress forbade annexation.  The naval base was established to maintain Cuban independence.

In 1917, President Woodrow Wilson bought the American Virgin Islands from Denmark for $25 million.  The US had first sought to purchase them in the 1860s.

In 1944, President Franklin Delano Roosevelt purchased Water Island for $10,000 from Denmark.  It was the last of the Danish Virgin Islands and was less than 1 square mile in size.  At the time of the sale, Denmark was occupied by the Nazis.

During World War II, the US used Greenland as a refueling stop.  In 1946, President Harry Truman offered to buy Greenland, but Denmark declined.  In 1951, the US established Thule Airbase - now Pituffik Space Base - as a missile warning base for the Cold War.

President Trump's offer to buy Greenland is nothing out of the ordinary.  Clearly, the US has purchased a lot of territory with varying degrees of arm-twisting.  Greenland has been on the wish list for more than 150 years.