Cautionary words from President Biden, who says the US shall respond after iranian backed militants killed three american service personnel and injured at least 30, all stationed in Jordan. They are the first american service members to die from hostile fire since the start of the Israel Hamas war. The troops were there to support american forces in Syria and assist the military in Jordan. Their post is called Tower 22. Officials say it was hit by a one way drone. Some of the wounded are being treated for serious shrapnel wounds. Others are being examined for traumatic brain injury. Since the Israel Hamas war, iranian backed militants have repeatedly carried out strikes from Iraq, Syria, and notably Yemen, where the US and its allies have intercepted dozens of missiles and drones. Iran's foreign minister told our Martha Raditz just days ago that no one would benefit from a wider war. Tonight, the White House is walking a fine line between fighting back and risking a larger conflict. ABC senior White House correspondent Selena Wang.

Leads us off tonight. The first american troops killed by enemy fire since the start of the Israel Hamas war. The White House blaming Iran backed militants for the deadly drone attack on a us base in Jordan near the border with Syria. Three Americans at Tower 22 base were killed and at least 30 were injured when the drone strike made it through the base's air defenses. The Pentagon says some of those injuries are serious, including shrapnel wounds and possible traumatic brain injuries. President Biden addressing the attack today at an event in South Carolina, vowing to hold those responsible accountable.

We had a tough day last time in the Middle east. We lost. We shall respond.

Iranian backed militants have launched more than 150 attacks on us forces in the region since October. The US has retaliated several times with strikes of its own. Just this week, ABC's Martha Raditz pressed the highest ranking us military officer on the administration's strategy.

What would you say to those people who are critics who would say, look, they're not being tough enough on these militants, they're not being tough enough on Iran.

I would also ask, do they want a broader conflict? Do you want us in a full scale war? And so we've got to be thoughtful about our approach in these areas. And we can't predict exactly how any one of these groups is going to respond. We don't want to go down a path of greater escalation that drives to a much broader conflict within the region.

That ever present risk of military escalation. Selena Wang joins us now from the White House. Selena, now that american troops are dead, we're already seeing increased pressure on the Biden administration to respond.

Exactly, Lindsay. The pressure is growing. Republican lawmakers, including Mitch McConnell and House Speaker Mike Johnson, they're calling on the president to take stronger action to stop these attacks. Now, U. S. Officials tell me tonight that they do expect a serious response from the Biden administration. But, look, the president here is walking a very fine line. He's trying to deter these attacks from these iranian backed militant groups while also trying to prevent this conflict from spreading.

Lindsay, Selena from the White House. Thanks so much, Selena.

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