In a press briefing on Sunday’s attack, the Pentagon named those killed as William Rivers, Kennedy Sanders, and Breonna Moffett, all from an army reserve unit in the state of Georgia.
Speaking after her identity was released, Ms Sanders’ parents paid tribute to their daughter, saying she had been eager for a chance to see a different part of the world.
“She was loved. She didn't have any enemies. All the time you saw her smiling," her father, Shawn Sanders, said.
“This is somebody who was just living life, enjoying life at a young age, working toward a career."
The president has vowed that the US “shall respond” as Iran-back fighters in eastern Syria reportedly began evacuating their posts fearing air strikes.
Pentagon officials said on Monday at least 40 US troops were also said to have been injured in the strike on the support base known as Tower 22.
The brazen attack risks inflaming tensions in the Middle East as the Biden administration tries to keep the Israel-Hamas war from expanding into a broader regional conflict.
“The president and I will not tolerate attacks on US forces, and we will take all necessary actions to defend the US and our troops," US defence secretary Lloyd Austin said on Monday as he met Nato secretary-general Jens Stoltenberg.
According to US media reports, American forces may have mistaken the enemy drone for an American one and let it pass unchallenged into the base.
As the enemy drone was flying in at a low altitude, a US drone was also returning, meaning there was no effort to shoot down the other drone, reported the Wall Street Journal.
Asked if the failure to shoot down the enemy drone was "human error," Pentagon spokeswoman Sabrina Singh said that the US Central Command was still investigating.
The US has vowed to punish the attack, but the Biden administration has stressed that it is not seeking to escalate the ongoing conflict.
An umbrella group for Iran-backed factions known as the Islamic Resistance in Iraq has claimed dozens of attacks against bases housing US troops in Iraq and Syria since the Israel-Hamas war began.
On Sunday, the group claimed three drone attacks against sites in Syria, including near the border with Jordan, and one inside of “occupied Palestine".
However, it has so far not claimed the attack in Jordan.