Back in 2006, when he was still the junior senator from Illinois, Barack Obama found himself in Metropolis, a small town in the south of his state. A photo survives of Obama in front of the town's giant Superman statue, the then-senator mimicking the Man of Steel's pose. Never mind the ammunition that picture has been providing ever since to both the president's friends and his foes. What the geography-obsessed among us want to know is: What is Metropolis doing on the banks of the Ohio River?
The town's connection with the Last Son of Krypton is post-hoc  : Metropolis was founded in 1839, almost a century before Superman was conceived. It was named with something else entirely in mind. As the likely location where the New Orleans & Ohio Railroad would cross the river on its way to Chicago, the fledgling town was hoped to become, in quick succession: a traffic hub, the nucleus of a western District of Columbia, and eventually the new capital of a westward-expanding nation . As place-names go, Metropolis is both grand and bland -- generic enough for an as yet nonexistent capital city.
Western D.C. never came to be , but the idea of moving the capital to a more central location isn't as harebrained as it might sound. After all, the Founding Fathers chose the site of eastern D.C. because it was near enough to the geographical center of the original 13 states. This was partly because North and South begrudged each other the chance to host the capital, but also because centrality has a bunch of practical advantages .
As the American Empire took a westward course, so did the country's geographical center. It moved away from Washington, D.C., zipping past Metropolis along the way. Until the admission of Alaska and Hawaii as full-fledged states, the center of the United States was usually situated near Lebanon, Kansas. After 1959, it moved to 20 miles north of Belle Fourche, South Dakota. America's center and capital are now over 1,400 miles apart. To put that in perspective: Cancun, Mexico is closer to Washington's corridors of power than Belle Fourche .
At present, nobody  is advocating that the three branches of the federal government uproot themselves from the banks of the Potomac to set up shop on the desolate Dakotan flatlands. Politicians from both parties ritually profess the desire to change the way Washington works; neither wants to change where the national government works. But what sounds impossible in the United States has been done elsewhere in the world.
Plenty of other countries have moved their capital, invariably to a more central location. A practical rationale recurs everywhere: countries are governed more efficiently from the center. But a central capital also has symbolic value. Its location subtly reinforces the raison d'état: this country is a "natural" unit, its political borders are as they should be, and its capital radiates power evenly across its entire domain .
Even in the era of instant communication, the interplay between practical and symbolic value of "capital centrality" still holds. It creates a symbolic center of gravity with practical, bricks-and-mortar consequences: new roads and airports will point towards the new capital, minimizing the difference in average distance that national representatives need to travel to their parliament .
By accident of history, some countries are endowed with such capitals: France's traditional centralism owes much to the relative centrality of Paris ; in spite of its many border changes, Poland's capital Warsaw manages to be relatively close to the country's geographic center of gravity ; and Brussels looks to be slap bang in the geographical heart of Belgium . Midway between Nepal and Burma, Bangladesh's capital Dhaka is near the country's geographical center. Windhoek, Namibia's capital, is so close to that country's midpoint that nobody seems to have bothered calculating where it actually is. And Minsk is only 22 miles north of Belarus's geographical midpoint, the museum town of Dudutki. But the kicker has to be Madrid, only 6 miles north of the actual center of Spain, at Cerro de los Angeles .
Less fortunate nations have sometimes chosen to right a geopolitical wrong by moving their geographically eccentric capital to a more central location. But as some of the examples below show, such transplants are in serious danger of rejection by the body politic. For the symbolic charm and practical advantages of a centrally placed capital are quite often ephemeral, and perhaps for good reason: settlement occurs not because a location is central, but where it is deemed advantageous. Still, the urge to recalibrate national capitals cuts across so many cultures that it may be deemed to represent a universal human trait -- the never-ending tension between the attraction of the obvious and the urge to plan something better.
 In 1972, DC Comics (and, a few months later, the Illinois State Legislature) declared Metropolis, Illinois, to be the "hometown of Superman." Ironically, numbering only a few thousand residents, the town bears more resemblance to Clark Kent's hometown of Smallville than to the big city of Metropolis, where he went to pursue joint careers in journalism and heroism.
 In which case the name Metropolis would again have been a misnomer: its etymology suggests a Greek Mother City, like Athens or Sparta, spawning a string of colonies. Had Metropolis become the nation's capital, the former one, Washington, D.C., would have been the metropolis.
 A planned Capitol City, across from Metropolis on the Kentucky side of the Ohio River, never made it off the drawing table.
 "[... T]he search for a geographic location, cast in terms of geographic centrality, rested on the conviction that the capital had to be as near and as easily accessible through central location to the citizens as possible. The greatest possible centrality would preserve the electorate's ability to watch over its representatives, improve representation, and limit corruption." Jason S. Kassel: Constructing a Professional Legislature: The Physical Development of Congress, 1783-1851.
 The population center of the United States, by the way, has also shifted west-southwest since the 1930s. And it keeps moving. In 2010, it was 2.7 miles northeast of Plato, Missouri. By 2020, it is projected to be around 10 miles north of Hartville, Missouri.
 Public opinion being the many-splendored thing it is, probably not nobody. But apart from the Belle Fourche Chamber of Commerce -- not an awfully large crowd.
 This chimes with the theory of the axis mundi, a central location where heaven and earth supposedly connect. Examples include sacred mountains (Fuji, Kailash, Ararat), but also capital cities: Cuzco is Inca for "navel," and Rome's road network radiated from a location called the Umbilicus. See also .
 This may seem abstract, but it has practical implications -- in fact, it was the stuff of the so-called expenses scandal in Britain a few political seasons ago. As some members of Parliament need to travel extremely far to get to London, they could claim compensation for second residences in the capital. But since many from the densely populated southeast live within commuting distance, quite a few of their second homes were not really needed -- opening up all sorts of possible avenues of misuse, like renting out the government-sponsored second home for personal gain.
 The honor of being France's most central location is disputed by at least 10 villages, in the départements of Allier and Cher.
 Usually placed at Piatek, under 70 miles west of the capital.
 The actual geographical center of Belgium is near the little town of Walhain, 25 miles southeast of Brussels.
 And not the Puerta del Sol, in the center of the city, as some sources claim. That would have been a bit too neat, as this is where the Kilómetro Cero is located, the zero mile marker for all official road distances in Spain.
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