reporter: under cover of darkness, three air force cargo jets, escorted by f-18s, dropped pallets like these, loaded with thousands of gallons of water and meals ready to eat. with the isis threat out there, our crews will be in some danger by doing these air drops. reporter: those isis terrorists have surface-to-air missiles and a slew of firepower. they re threatening to take control of the largest electric dam in the country and are closing in on erbil. the kurdish capital has key american outposts with hundreds of military consultants and a consulate. i ve directed our military to take strikes against isil convoys should they move toward the city. reporter: the strikes have not begun. but u.s. commanders have a green light. if we go into air strikes, we re opening another chapter on a book the white house had hoped they had closed. reporter: the last u.s. troops pulled out of iraq in 2011. president obama says he does not plan to send combat troops back
fighters are taking control of iraq. now threatening the capital of the kurdish region, erbil, where america has a key outpost, with military consultants and a consulate. if the militants threaten, a u.s. official says the u.s. is ready to strike. but a humanitarian mission is already under way. three air force cargo jets dropping critical aid, food and water. it is a race to stop a catastrophe. at least 10,000 people, families who fled to the top of a mountain, now collapsing from blistering heat, pleading there is no water, no bread. nearly 20 children already dead. they are trapped atop this mountain 3,000 feet up, with no escape because down below isis terrorists have taken over their homes, warning of a slaughter if they return. that is barbaric.