A journey into one of the most remote and dangerous countries in the world ... Djibouti is a tiny state of citrus-colored shacks and goat-lined boulevards tucked into a barren, volcanic stretch of the Horn of Africa. It sits astride the narrow straits that lead to the Red Sea and the Suez Canal, and is home to the U.S.'s only permanent military base in Africa, Camp Lemonnier, linchpin of one of the Obama administration's most secretive and controversial programs: the drone-based campaign of surveillance and assassination against Al Qaeda and its allies in Somalia and Yemen. ... as Yemen has become the latest country in the Middle East to descend into a full-fledged civil war. In March, after Houthi rebels seized control of the government, a coalition of Arab states led by Saudi Arabia, which accuses the Houthis of being supported by its archrival Iran, launched a U.S.-supported campaign of airstrikes and imposed a land, air and sea blockade of the country — which it says is necessary to keep out Iranian weapons. ... Four months of bitter fighting later, the Houthis control even more territory. And the conflict has pushed this already impoverished country to the brink of a massive humanitarian catastrophe, with the aid community warning of an impending famine if the blockade is not lifted. ... Meanwhile, Al Qaeda has taken advantage of the chaos to seize wide swaths of eastern Yemen, including the port city of Mukalla, and has called for new attacks against the U.S. ISIS has gained a foothold and launched car-bomb attacks in the capital. Forced to evacuate its embassy and 125 special-operations advisers, the U.S. found its counterterrorism strategy in shambles, with many of the weapons and equipment it supplied to Yemen reported to be in the hands of militias.