In the shadow of the Sept. 11 attacks, the United States rushed troops and military aid to a swath of West Africa to help French forces stop the spread of Al Qaeda and other terrorist groups.
More than a decade later, and with hundreds of millions of dollars in security assistance spent, that regional counterterrorism effort has largely failed.
Groups that have declared allegiance to Al Qaeda and the Islamic State are on the march. Military coups have toppled civilian-led governments in Mali, Guinea, Burkina Faso and Niger. The new leaders have ordered American and French troops out, and in some cases invited Russian mercenaries in to take their place.
As the United States withdraws 1,000 military personnel from Niger and shutters a $110 million air base there by September, American officials are scrambling to work with a new set of countries in coastal West Africa to battle a violent extremist insurgency that they perceive is steadily seeping south.
“Of course, it’s frustrating,” Christopher P. Maier, the Pentagon’s top official for special operations policy, said in an interview. “Our general desire to promote democratic governments and having healthy governance there has not gone particularly well.”
The U.S. military has had more success training local counterterrorism troops, Mr. Maier said, although some participated in the recent military takeovers. But, he added, “it’s disappointing when we’ve invested in that relationship and then we’re asked to depart.”