When Adm. Eric Olson, the former leader of U.S. Special Operations Command, wanted to explain where his forces were going, he would show audiences a photo that NASA took, titled "The World at Night." The lit areas showed the governed, stable, orderly parts of the planet. The areas without lights were the danger zones – the impoverished, the power vacuums, the places overrun with militants that prompted the attention of elite U.S. troops. And few places were darker, in Olson's eyes, than East Africa.

Quietly, and especially over the last two to three years, special operations forces have focused on that very shadowy spot on NASA's map (see below). The successful Tuesday night raid to free two humanitarian aid workers from captivity in Somalia is only the most recent and high-profile example. More and more elite forces have transited through a mega-base in Djibouti that's a staging ground for strikes on al-Qaida allies in the Horn of Africa, especially in Somalia.

It's not quite the new Pakistan, or even the new Yemen, but it's close – especially as new bases for the U.S.'s Shadow Wars pop up and expand. The U.S. military sometimes seemed like it was casting about for a reason to set up shop in Africa. Counterterrorism has given it one.

Fighting Somalia's pirates might get most of the media attention. But the U.S. is much more concerned about al-Shabab. The al-Qaida aligned movement seeks to depose the Somali government, recruits from radicalized American Muslims and may have sought to bring terrorism back to U.S. shores. Just across a very narrow Gulf of Aden is Yemen, the home of al-Qaida in the Arabian Peninsula, which has repeatedly tried to attack America.

In 2009, the top U.S. intelligence official pointed to Yemen and "parts of Africa" where al-Qaida's leadership might "relocate" if it lost its Pakistani safe haven, to "exploit a weak central government and close proximity to established recruitment, fundraising, and facilitation networks." His successor told Congress in 2011 that al-Shabab would "probably grow stronger... absent more effective and sustained activities to disrupt them."

That's where the forces Olson used to run came in.

Located northwest of Somalia is a former French Foreign Legion base in Djibouti called Camp Lemonnier. The U.S. military has been there for a decade. It's a resupply point for U.S. ships passing by, as well as the home of a multinational, American-led counterterrorism team called the Combined Joint Task Force-Horn of Africa.

Recently, more and more special operations forces have called it a temporary home. Camp Lemonnier was where the commando team took hostages Jessica Buchanan and Poul Thisted for medical care after freeing them. But the camp is much more than just a big medical facility: it's also a staging ground for the growing Shadow War in Somalia – and particularly a drone war over it.

Much of the day-to-day fight against al-Shabab is outsourced to African peacekeepers. But the raids and strikes that U.S. commandos have launched against specific Shabab targets are becoming more frequent. Cruise missiles and even, apparently, U.S. helicopter strikes have also hit the group. Special operators even launch raids at sea: this spring, they captured captured one Shabab affiliate, Ahmed Abdulkadir Warsame, offshore in the Gulf of Aden before detaining him for weeks aboard the U.S.S. Boxer.

Then comes the drone war. Lemonnier isn't the only U.S. base near the Horn. Throughout the last decade, the military ran a smaller special-operations base in Kenya and another in Ethiopia. Now an Ethiopian outpost will become a launchpad for U.S. drones, as will a facility nearby in the Seychelles, all to launch strikes against al-Qaida allies in East Africa. The most recent of them struck Sunday outside Mogadishu, killing a British-born militant.

Nor is the military the only U.S. organization at work in east Africa. Somalia has attracted the CIA as well, which runs a secret prison attached to the Mogadishu airport. During earlier iterations of the CIA's post-9/11 involvement in Somalia, it blustered that its operations were protected by drones that actually weren't overhead – all while it assembled a coalition of friendly warlords to help fight al-Qaida. Nor has the FBI been left out of the action: it worked with the special operations forces to free Buchanan and Thisted on Tuesday night, although Navy Capt. John Kirby, a Pentagon spokesman, said no FBI personnel accompanied the raiding team.

Another dramatic expansion of U.S. power in Africa, however, may have been hiding in plain sight.

When President George W. Bush created the U.S. Africa Command in 2007, it wasn't really clear what the organization was. Humanitarian aid dispensary? Laboratory for African troops to train with their U.S. counterparts? Vehicle for Americanization of Africa's wars?

The question hasn't totally been settled. But Africa Command has had a very busy year. In March, it led the initial phase of the U.S./NATO war on Moammar Gadhafi, launching a fusillade of Tomahawk missiles, flew jamming jets and operated conventional ships, subs and fighter jets before handing the war off to a Canadian general. In October, it sent a small advisory force to central Africa to help combat the brutal Lord's Resistance Army.

Its leader, Army Gen. Carter Ham, hasn't been in charge for a full year yet, but his busy schedule thus far was capped by last night's Somalia raid – for which he was the senior-most officer in command, according to the Pentagon. The raid is a sign that Africa Command places great emphasis on its relationship with the U.S.' elite forces, who, tacitly, help entrench the command's relevance.

That's going to remain the case as long as a decimated al-Qaida relies on proxies like al-Shabab to retain its own relevance. And it's going to remain the case as long as Obama leans on special operators and the CIA to prosecute his Shadow Wars, which pursue terrorists indefinitely even while Obama draws down the large land wars in Iraq and Afghanistan. When looking at where counterterrorism goes next, it helps to squint at the obscured places on Olson's map.

Photos: David Axe, NASA