“We will carry on their commitment to fight terrorism. And have no doubt – we will hold all those responsible to account at a time and in a manner of our choosing,” Biden said in his statement released by the White House.
Republican opponents of Biden seized on the attack as evidence of the Democratic president’s failure to confront Iran as its proxies strike against US forces across the region.
“The only answer to these attacks must be devastating military retaliation against Iran’s terrorist forces … Anything less will confirm Joe Biden as a coward,” said Republican Senator Tom Cotton in a statement.
A senior official with the Iran-backed Palestinian militant group Hamas, Sami Abu Zuhri, directly tied the attack to Israel’s campaign in Gaza.
“The killing of three American soldiers is a message to the US administration that unless the killing of innocents in Gaza stops, it must confront the entire nation,” he told Reuters.
“The continued American-Zionist aggression on Gaza is capable of exploding the situation in the region.”
The US military said the attack occurred at a base in northeastern Jordan, near the Syrian border. It did not name the base. US military activity in Jordan can be a sensitive issue, particularly at a time of heightened tensions of the Israel-Hamas conflict.
A Jordanian government spokesman told state TV that the militants targeted a different base, outside Jordanian territory.
Washington has given Jordan around US$1 billion to bolster border security since Syria’s civil war began in 2011, and has recently sent more military aid to that end, Western intelligence sources say.
It is unclear which Iran-backed group may have carried out the attack but several US officials said they did not believe that Iranian military forces themselves launched the one-way attack drone.
“While we’re still gathering facts, this is most assuredly the work of an Iranian-backed militia group,” another US official said.
