Michael O’Hanlon is the Philip H. Knight chair in defense and strategy at the Brookings Institution and author of “To Dare Mighty Things: U.S. Defense Strategy Since the Revolution.”
Although President Donald Trump is pushing the limits of executive-branch power in many areas of public policy and the law, he cannot take Greenland by himself.
Clear precedent establishes that Congress must have a role in any annexation of territory by the United States — after all, this country has done it lots of times in the past. Even though Trump has had considerable sway over the Republican Party and therefore Congress in his second term, enough GOP voices have publicly opposed a takeover of the huge island to our north that any attempt to make Greenland formally part of the U.S. would surely be voted down.
Yes, Trump could probably disregard Congress’s constitutional prerogative to declare or authorize military operations and launch a military mission to occupy parts of Greenland on his own. There is a long history of presidents failing to consult Congress or gain authorization for a significant military operation: Harry S. Truman in the Korean War, Lyndon B. Johnson in Vietnam (notwithstanding the fig leaf of the Gulf of Tonkin Resolution), George H.W. Bush in Panama, Barack Obama in Libya, Trump himself in Iran and Venezuela.
Trump could assert that any operation in Greenland does not reach the threshold of combat operations as specified in the 1973 War Powers Act, and given precedent, it is doubtful that this (or any) Supreme Court would force him to halt such an operation on any given time frame. That such an operation would strike many as extra-constitutional would not be enough to prevent it.
In acquiring territory from other nations, however, the U.S. has always required that Congress play a role. In two cases, clever policy entrepreneurs had to find a method that bypassed the need for a two-thirds majority vote in the Senate, as required for any treaty, but even in these cases, Congress approved the acquisitions. It has also, of course, provided the necessary funds either to purchase the lands in question and/or to govern them thereafter.
In the outright purchase of the Louisiana Territory from France in 1803 and of Alaska from Russia in 1867, the agreements were considered treaties with foreign governments and were therefore formally approved by a two-thirds majority vote in the Senate. The same was true of the 1819 purchase of Florida from Spain, with the Senate ratifying in 1821 (and of the Oregon Treaty of 1846 divvying up the Pacific Northwest with Great Britain).
In two other notable cases, the acquisition of lands following the Mexican-American War and the Spanish-American War, the Senate approved peace treaties that included the (coercive) land sales that resulted from the conflicts. In the Mexican-American War, the U.S. obtained most of its present southwest; in the Spanish-American War, it gained Puerto Rico and Guam, as well as Cuba and the Philippines on a temporary basis. Congress had also declared war with majority votes in both houses before each conflict (even if, in the latter case, few in Congress or the executive branch quite expected the U.S. to be left holding on to the Philippines at war’s end).
The acquisitions of newly independent Texas in 1845 and of Hawaii in 1898 were a bit more complex because they were more controversial — the first because it involved the question of slavery’s expansion, and the second because of partisan differences regarding the country’s approach to gaining Hawaiian support for annexation (involving as it had the overthrow of Queen Liliuokalani in 1893). Lacking the votes to gain Senate ratification, Presidents John Tyler and James K. Polk in the Texas case and William McKinley in the Hawaii case contented themselves with joint resolutions (by simple majority vote) in both houses of Congress. There was never a successful court challenge to this mechanism.
In no case, therefore, has any previous American president enlarged the country simply through executive action or authority.
Even if Trump put U.S. forces ashore in Greenland (probably without violence but still with the risk of casualties given the austere operating environment), he could not make the island part of the U.S. on his own, and a future president would most likely withdraw the military at a later date, undoing the attempted acquisition.
Republican members of Congress should remind Trump of this history before he goes much farther down the rabbit hole on Greenland. Perhaps Congress would fund a truly consensual purchase of the island if the president could pull off a miracle and persuade both Denmark and Greenland to entertain the possibility.
Short of that, Greenland will not become part of the U.S. simply because Trump wishes it so.
The post Trump can’t grab Greenland all by himself appeared first on Washington Post.
