“Where’s my jet pack, dude?” is a common whine about how supposedly disappointing 21st-century technology is turning out to be.

No matter that we all carry a pocket communicator/computer/library beyond the imagining of any 20th-century science-fiction writer; our real yearning, it seems, is a more ancient one: to fly like Icarus, who in Greek mythology flew—and crashed—using wings made of feathers and wax.