Is the U.S. "operating 'floating prisons' to house those arrested in its war on terror"? The Guardian reports this morning that "the U.S. may have used as many as 17 ships as 'floating prisons' since 2001." Of course, the "floating prison" in this specific case is simply a warship – but actual, purpose-built floating prisons do exist, for instance, in Amsterdam. There, an illegal-immigrant detention center "sits on two concrete platforms, each in turn moored to large steel pilings," moving up and down with the tides, like a building only temporarily docked on the edge of the city. Bryan Finoki calls this the "ongoing narrative of sea-bound detention," drawing parallels between this and the practice of extraordinary rendition, wherein detainees are shipped through the skies of the world inside unmarked airplanes. So are airborne prisons far off? Clusters of hot air balloons in the mid-Pacific, "moored" to the Trade Winds, in a strange, post-sovereign airspace outside the reach of international law.