Who would win in a war: 1 billion lions or the US military’s ground force?

US military ground force only- no air force, no navy, and no armored vehicles. They can use explosives that can be launched using handheld weapons (I.e. RPGs and grenades are fair game, nukes are not). The lions are aware of the war and their mission- they can organize and communicate among themselves. Surrendering is not an option- every lion or every serviceman must be eliminated. Procreating or adding forces is not permitted by either side, and they can’t get support from other countries/species. The war takes place in Africa in the lions natural habitat.