From November 2015 to 2019, the United States and allies carried out a large series of both airstrikes and drone strikes to intervene in Libya in its revived conflict in support of the Tripoli-based Government of National Accord against the ISIL presence in the region. By 2019, the ISIL branch had been largely driven from holding Libyan territory, and US strikes ceased.
Background
Military action against ISIL
On 13 November 2015, the United States launched an airstrike in Derna, Libya. Two U.S. F-15E fighter jets targeted senior ISIL leader Abu Nabil al-Anbari in the airstrike, who was the top ISIL commander in Libya. In January 2016, ISIL's Libyan faction confirmed Abu Nabil's death in a eulogy to him.
Obama Administration officials were weighing a new campaign plan for Libya that would deepen the United States' military and diplomatic involvement, on yet another front against ISIL. The United States and its allies are increasing reconnaissance flights and intelligence collecting there—and even preparing for possible airstrikes and raids, according to senior American officials. Special Operations forces met with various Libyan groups near the end of 2016 to vet them for possible action against ISIL.
On 19 February 2016, US warplanes carried out an airstrike on multiple ISIL targets in Libya, hitting an ISIL training camp and a senior extremist leader, the training camp was near Sabratha, Libya, 60 people were present at the camp at the time of the strike, more than 40 people were killed with more wounded, some critically, On 14 February 2016, a U.N.-designated council presented a new 18-member Libyan cabinet in the Moroccan city of Skhirat, weeks after an earlier lineup was rejected. The internationally recognized parliament has to endorse the new unity cabinet. If approved, the new unity government could eventually seek international military intervention against ISIL extremists who have taken advantage of the country's political vacuum since 2014.
On 1 August 2016, U.S. crewed and uncrewed aircraft carried out airstrikes on ISIL targets in Libya, responding to the U.N.-backed government's request to help push the militants from their former stronghold of Sirte (where several hundred ISIL fighters remained), in what U.S. officials described as the start of a sustained campaign against the extremist group in the city. President Barack Obama authorized the airstrikes after a recommendation by U.S. Secretary of Defense Ash Carter; the strikes hit an ISIL tank and two vehicles that posed a threat to forces aligned with Libyan GNA (Government of National Accord). This was the third U.S. air strike against ISIL militants in Libya, but this time U.S. officials said it marked the start of a sustained air campaign rather than another isolated strike, U.S. airstrikes would continue to target ISIL in Sirte in order to enable the GNA to make a decisive, strategic advance. United States Africa Command (AFRICOM) oversaw the US effort, which was known as Operation Odyssey Lightning. AV-8B Harrier IIs assigned to the 22nd Marine Expeditionary Unit (22nd MEU) flying off conducted the airstrikes and uncrewed aircraft launched from undisclosed locations. Airstrikes continued, on 2 August, airstrikes hit a rocket launcher, an excavator and a pickup truck with a mounted recoilless rifle and on 3 August airstrikes struck a pickup truck with a mounted recoilless rifle; by 9 August the U.S. conducted 28 strikes against ISIL in Libya, with more than half of the strikes being conducted from uncrewed aircraft. By 16 August, U.S. airstrikes hit an ISIL vehicle and 4 militant positions in Sirte, bringing the number of U.S. airstrikes in Libya to 48. On 17 August, U.S. Africa Command officials announced on 16 August airstrikes on ISIL targets in Sirte struck 7 enemy fighting positions, 4 vehicle-borne bombs, 1 pickup truck with a mounted recoilless rifle, 12 enemy fighting positions and 1 command-and-control vehicle, bringing the total number of airstrikes in support of Operation Odyssey Lightning to 57. On 22 August, Stars and Stripes reported that U.S. Marine AH-1W SuperCobra helicopters participated in strikes against ISIL militants in Sirte on 20 and 21 August; a small detachment of U.S. special forces in Sirte provided most of the targeting information for the airstrikes which were then relayed to U.S. forces through Libyan government troops. On 31 August, Stars and Stripes reported that the U.S. military conducted 104 airstrikes against ISIL targets in Libya in August.