Since 2007 the United States has created and expanded AFRICOM (Africa Command) to manage all the increasingly numerous American military operations in Africa. Since most of these operations involved special operations forces rather than conventional military forces AFRICOM released little detail on what was where. But in the last few years more of these details have emerged. As suspected most of the 40-50 AFRICOM “bases” detected are not bases in the traditional sense but merely temporary agreements to use existing civilian or military airbases or other facilities in African nations. These are usually countries where AFRICOM is providing assistance in dealing with Islamic terrorist activity or other security threats. As of 2016 there were about 46 of these AFRICOM facilities located in 24 African countries. About two-thirds of these facilities are considered temporary or “contingent” (there are arrangements to use an airbase or port facility if needed and on short notice). The permanent operations are bases or FOS (Forward Operating Sites) while the temporary sites are CSLs (cooperative security locations) where American and local forces operate together or CLs (contingency locations) where arrangements have been made for use if needed. About half the AFRICOM sites are CLs and not used by Americans on a regular basis.
AFRICOM is similar in organization to other commands (CENTCOM, for the Middle East, and SOUTHCOM, for Latin America, etc). Before AFRICOM was created those operations were coordinated between two other commands (the one covering Europe and the one covering Latin America). The establishment of AFRICOM means more money for counter-terror operations in Africa and more long range projects. No country in Africa had sufficient infrastructure for AFRICOM headquarters and few wanted to risk the political blowback from hosting a major American military headquarters.
In late 2016 construction began on a new AFRICOM base in Agadez, Niger, 730 kilometers northeast of the capital (Niamey). The U.S. had received permission from Niger for such a base in 2014, a year after American UAVs began operation from a Niger military base next to the Niamey airport. The new Agadez base is built largely from scratch because, unlike Niamey, Agadez does not have a large airport or much in the way of support for lots of aircraft operations. Agadez is closer to Chad, southern Libya and Nigeria, where American aerial surveillance is more in demand by the local governments. Agadez will also apparently support armed UAVs as well. The U.S. will continue to supply intelligence obtained by the Niger-based UAVs with Niger and other nations in the area that have intelligence sharing agreements.
Agadez will be the second American airbase in Africa and, like the first one, shared with France and other allies. The first U.S. base was established in 2002 when the United States began sharing an old French base in Djibouti (the northwestern neighbor of Somalia). Since then Djibouti has hosted the one official U.S. military base (Camp Lemonnier) in Africa. France and the United States SOCOM (Special Operations Command) have had special operations forces (commandos and special aircraft) outside the Djibouti capital since 2002. In 2014 the U.S. signed another ten year lease for that base. U.S. forces in Djibouti were increased after resistance collapsed in Iraq in 2008 and the base became the command post for a network of American operations through the region. Most of the effort is directed at monitoring what is going on in the region (mainly Somalia and Yemen but also Eritrea, Nigeria, Mali, Libya, Kenya, and Ethiopia) not at interfering with the local terrorists. Not much, anyway. The Djibouti base also supports operations throughout the Sahel (the semi-desert strip between the North African desert and the Central African jungles, which stretches from the Atlantic to Somalia).
By 2013 Camp Lemonnier and nearby airfields supported fourteen large UAVs (ten MQ-9 Reapers and four MQ-1 Predators), six manned U-28 aircraft and eight F-15E fighter bombers. The two seat F-15Es carried surveillance gear and could fly long distances, find a target and destroy it with a GPS or laser guided weapon. In addition U.S. Navy ships off the African coast sometimes had MQ-8 and ScanEagle UAVs operated from ships to search inland. The U.S. Navy also had two P-3C maritime patrol aircraft stationed near Camp Lemonnier. More aircraft arrived after 2014, when ISIL (Islamic State in Iraq and the Levant) and al Qaeda became more active in North Africa and Yemen. The number and composition of foreign aircraft varies according to local needs.