Al-Shabaab is a terrorist group affiliated with al-Qaeda.
The US Africa Command, which oversees US military operations on the continent, said the airstrike was "carried out in response to an attack by a large group of Al-Shabaab" militants against the Somali armed forces "on January 19 ". The US military said, "Currently, this air strike killed fifty-two (52) militants" and they judge that no civilians were killed or injured in the strike.
On 15 January, Shabaab recently assumed responsibility for a terrorist attack in Nairobi, Kenya. Men armed with weapons and explosives stormed a hotel complex in the Kenyan capital that killed at least 21
The US Department of Defense estimates that there are 3,000 to 7,000 al-Shabaab fighters and 70 to 250 ISIS fighters in Somalia (as of August 2018).
In America, the air strikes in Somalia have increased significantly since President Donald Trump has authorized the US military to make a precision strike. In March 2017, Al-Shabaab will be targeted to strengthen the federal government in Somalia. Previously, the US military was only authorized to conduct air strikes to defend advisers on the ground.
The Saturday strike is the sixth US air strike in Somalia, which targeted al-Shabaab in 2019. In 2018, the US led 47 precision air strikes against al-Shabaab fighters. In 2017, the US carried out 35 air strikes and 15 air strikes in 2016.
The US has about 500 soldiers in Somalia, mainly in advisory capacity.