NIAMEY, Niger — Nearly every day, and sometimes twice daily, an unarmed U.S. drone soars skyward from a secluded military airfield here, starting a surveillance mission of 10 hours or more to track fighters affiliated with al-Qaida and other militants in neighboring Mali.

The two MQ-9 Reapers that are based here stream live video and data from other sensors to U.S. analysts working with French commanders, who say the aerial intelligence has been critical to their success over the past four months in driving jihadists from a vast desert refuge in northern Mali.

The drone base, established in February and staffed by about 120 members of the Air Force, is the latest indication of the priority Africa has become for the U.S. at a time when it is winding down its presence in Afghanistan and President Barack Obama has set a goal of moving from a global war on terrorism toward a more targeted effort. It is part of a new model for counterterrorism, a strategy designed to help local forces — and in this case a European ally — fight militants so U.S. troops do not have to.

But the approach has limitations on a continent as large as Africa, where a shortage of resources is chronic and regional partners are weak. And the introduction of drones, even unarmed ones, runs the risk of creating the kind of backlash that has undermined U.S. efforts in Pakistan and provoked anger in many parts of the world.

The increase in the number of potential threats in the region was made clear to Obama during his visit to Africa last week.

“We need in Africa, not just in Senegal but the whole of Africa, to have the military capacity to solve this problem, but we need training, we need materials, we need intelligence,” President Macky Sall of Senegal told Reuters after meeting with Obama in Dakar to discuss fears of a growing violent Islamist threat in the Sahara.

The U.S. military, however, has only one permanent base in Africa, in Djibouti, more than 3,000 miles from Mali, as well as a constellation of small airstrips, including in Ethiopia and Burkina Faso, for surveillance missions flown by drones or turboprop planes designed to look like civilian aircraft. The challenge for the U.S., with little experience in Africa, is a difficult one.

“The U.S. is facing a security environment in Africa that is increasingly more complex and therefore more dangerous,” said Michael R. Shurkin, a former Central Intelligence Agency analyst who is now at the RAND Corp. “Effective responses, moreover, require excellent knowledge about local populations and their politics, the sort of understanding that too often eludes the U.S. government and military.”

And the threats facing Niger are typical of the ones that worry Sall. The government of President Mahamadou Issoufou is struggling to stem a flow of insurgents across lightly guarded borders with Mali, Nigeria and Libya. On May 23, terrorists using suicide car bombs attacked a Nigerien military compound in Agadez and a French-operated uranium company in Arlit, both in the country’s north.

To experts on Africa, the possibility that the drones will yet cause a backlash remains real, especially if Islamic radicals make it an issue.

“The concern would be that a lot of the blowback would be through channels we can’t easily perceive, such as Salafist mosques,” said Alexis Arieff, an Africa analyst with the Congressional Research Service in Washington.

The U.S. acknowledged the drone deployment here in February — initially sending a single Predator aircraft and later faters, more capable Reapers — but since then it has released virtually no information about their missions, presumably to avoid raising their public profile. The Pentagon denied a request by The New York Times to interview the Air Force flight crews, logistics and maintenance specialists, and security personnel assigned here at a military airfield on the opposite side of the commercial airport in Niger’s capital.

Historic landing — The U.S. Navy conducted a historic flight test Wednesday off the coast of Virginia when an experimental bat-winged drone made an arrested landing aboard an aircraft carrier for the first time.

The flight of the drone, dubbed X-47B “Salty Dog 502,” could redefine naval aviation.

Landing on an aircraft carrier as it plies the ocean and pitches with the waves is considered an extremely difficult feat for even the most seasoned pilot. The X-47B was controlled almost entirely by computer.

“By evolving and integrating new technology like the X-47B and the unmanned aircraft to follow, carriers will remain relevant throughout their 50-year lifespan,” Secretary of the Navy Ray Mabus said in a statement.

Relying on pinpoint GPS coordinates and advanced avionics, the sleek drone digitally communicated with the carrier’s computers to determine speed, crosswinds and other data as it approaches from miles away.

— Los Angeles Times