The recent rescue of two hostages in Somalia by US Special Forces highlights the strategic significance of the American installation in Djibouti, which is being touted as a model for future US bases in Africa and elsewhere.
Camp Lemonnier, established in 2003 as the home of the Pentagon's Combined Joint Task Force/Horn of Africa, was described by US Defence Secretary Leon Panetta during a December visit to Djibouti as "the central location for continuing the effort against terrorism."
A month later, the former French colonial base served as the launching pad for the helicopter raid organised by the US Africa Command that killed nine Somali pirates and freed their American and Danish captives.The success of that mission was hailed last week by Michele Flournoy, the Defence undersecretary for policy. In a speech at a National Security Symposium in Washington, Ms Flournoy suggested that Camp Lemonnier exemplifies the new ways in which the US intends to project its power around the world.
A US military strategy for the coming years outlined recently by President Barack Obama puts emphasis on developing "innovative, low-cost and small-footprint" operations as Washington pursues "new partnerships with a growing number of nations, including those in Africa and Latin America."
Instead of mobilising massive military deployments such as those in Afghanistan and Iraq, the Pentagon will seek to economise during the next decade while still applying its muscle in support of American interests.
Development of more bases similar to but perhaps smaller and less conspicuous than Camp Lemonnier is consistent with the US objective of paring its military budget but remaining capable of intervening quickly and decisively throughout the developing world.
Camp Lemonnier's growing prominence reflects its acquired role as the de facto operational centre in Africa for Africom, the US military command that is formally headquartered in Stuttgart, Germany.
Soon after its launch five years ago, Africom undertook an embarrassingly unsuccessful round of consultations with African leaders concerning establishment of a permanent presence somewhere on the continent for the new military command.
Liberia was the only black African country that publicly offered to host Africom.
It has since become clear, however, that Djibouti is willing to serve unofficially in that capacity.
Some of the approximately 3,500 US personnel stationed at Camp Lemonnier carry out civic-engagement missions similar to the "hearts and minds" initiatives undertaken as part of the US war in Vietnam.
These doctors, veterinarians and engineers regularly provide health services and help improve local infrastructure in East Africa.
Last month, for example a Combined Joint Task Force medical unit worked with Tanzanian health personnel in delivering care to some 2,100 women and children in and near Mtimbwani.
But Camp Lemonnier's primary purpose is to combat militants in much of Africa that are judged to pose a threat to US interests and allies.
At the same time, Africom is increasingly overseeing fighting forces after having initially emphasised its "soft power" attributes. Africom's debut as a formidable military machine came when it directed the US air war in Libya that proved instrumental in achieving regime change there.
Djibouti, a country of less than a million inhabitants, has given the United States the option to lease Camp Lemonnier until at least 2020. Led by President Ismail Omar Guelleh, Djibouti's government welcomes the US military presence, which provides the poor country with an important source of revenue. Djibouti is also closely allied with Ethiopia, which ranks as a key US strategic partner in East Africa.
On its part, the US is clearly content to do business with Djibouti, even though the most recent State Department worldwide report on human rights cited multiple abuses by the country's authorities, including corruption, prolonged detention, denial of fair trial, and restrictions on free speech and labour unions.
For all its growing importance, Camp Lemonnier is not the only place in black Africa where the US conducts military operations.The Pentagon also flies drones from airfields in Ethiopia and the Seychelles while assisting Amisom forces in carrying out drone surveillance inside Somalia.