" In no class of warfare,” C. E. Callwell had written a hundred years earlier, about the “small wars” of the nineteenth century, “is a well organized and well served intelligence department more essential than in that against guerrillas.” The same qualities that made intelligence so important when countering guerrillas then—the difficulty of finding the enemy, of striking him, and of predicting his next move and defending against it—were increased a hundredfold when trying to counter terrorists in the age of electronic communication and car bombs. "

― Stanley McChrystal , My Share of the Task: A Memoir