CLAUDIA ROSETT visited Guantanamo and reports on what she saw: “To fly into the damp Caribbean heat of this U.S. naval base at Guantanamo Bay, Cuba, is to enter a place of multifaceted myth, a zone that continues to inflame the imagination of the world. And yet, when it comes to witnesses, monitors and the media, there is probably no more heavily trafficked detention center on the planet.”