JUDY WOODRUFF:

Jonathan declared a state of emergency last May, and the military flushed the insurgents from cities, only to see them regroup in forests and caves.

Boko Haram's fight for an Islamic state in northern Nigeria has terrorized the country for 4.5 years, leaving thousands dead and forcing thousands more to leave for their own safety. The violence now threatens the stability of Africa's largest oil-producing state. The U.S. is trying to help.

In October, American special forces held a two-week training session with the Nigerian military.

To tell us more about Boko Haram and what their recent attacks mean for Nigeria and the region, I'm joined by Peter Pham, who is director of the Africa Program at the Atlantic Council.

Welcome to the program. Tell us more about who and what Boko Haram is.

J. PETER PHAM, the Atlantic Council: Well, Boko Haram started well over a decade ago as a somewhat syncretistic, eccentric…