AP Photo

One day in late November, an unmanned aerial vehicle lifted off from Shindand Air Base in western Afghanistan, heading 75 miles toward the border with Iran. The drone's mission: to spy on Tehran's nuclear program, as well as any insurgent activities the Iranians might be supporting in Afghanistan. With an estimated price tag of $6 million, the drone was the product of more than 15 years of research and development, starting with a shadowy project called DarkStar overseen by Lockheed Martin. The first test flight for DarkStar took place in 1996, but after a crash and other mishaps, Lockheed announced that the program had been canceled. According to military experts, that was just a convenient excuse for "going dark," meaning that DarkStar's further development would take place under...