The study highlights failures during the conflict, including a lack of awareness of the sectarian dynamics in the country.
The spokesman, Navy Capt. William Urban, said Friday that the Jan. 1 airstrike targeted Jamal al-Badawi.
The militants were preparing to attack government and tourism facilities, army and police personnel and Christian churches.
Iraqi politicians and militia leaders are speaking out against the continued presence of U.S. forces in Iraqi soil.
The strikes were carried out in close coordination with Somalia's government and were "conducted to thwart al-Shabab.
NATO's foreign ministers reaffirmed their commitment to stay the course despite mounting Afghan casualties.
Senators voiced concern that the Pentagon's new defense strategy could hurt the counterterrorism mission in Afghanistan.
Special operations forces are responsible for conducting U.S. counter-terrorism missions in Afghanistan and elsewhere.
The planned 10 percent cut from U.S. Africa Command's total force of 7,200 troops will be carried out over several years.
President Donald Trump is nominating a Navy special operations veteran to be the nation's top counterterrorism official.