Joe Biden has attributed the attack to Iran-backed militia groups. ITV News Correspondent Robert Moore and Global Security Editor Rohit Kachroo report
President Biden must make an imminent decision, the most significant of his presidency.
Does he launch retaliatory strikes on Iran itself?
It would be a huge risk, one that could turn the tragedy of Gaza and the simmering conflict in the region into an all-out war engulfing the whole Middle East.
One option, clearly, is for the US to continue calibrated strikes on the proxy militias that Iran supports in Iraq, Syria, and Yemen. US aircraft and special forces could hit weapons depots, infrastructure and so-called HVTs - High Value Targets.
But there is a key problem with that approach.
It is being tried and is failing badly.
There have been approximately 160 militia attacks on US forces in the region since October 7.
America has responded with limited strikes in response, and they have made no difference. Arguably, the Islamist Tehran-backed proxies feel emboldened.
That's why in Washington President Biden is being urged by national security hawks in Congress to hit Iran itself, principally the Islamic Revolutionary Guard Corps, the Iranian force that helps to arm and mobilise the proxy militias.
Just look at some of the suggestions he is getting from Republicans who claim that bombing Iran is the only way to re-establish deterrence in the Middle East.
Furthermore, Senator Tom Cotton is taunting Biden, recommending that he launches "devastating military retaliation against Iran... anything less with confirm Biden as a coward unworthy of being commander-in-chief."
But that only raises the next question in this unfathomably complex regional crisis: What would Iran do in response to being directly attacked?
The biggest question for the CIA's Iran analysts right now is trying to understand if Tehran is looking for a conflict from which it can profit, or if it is seeking influence but not war.
Quite apart from the strategic questions is the issue of the domestic politics of attacking Iran.
This is an election year in America. Does Biden gain more from being measured and calibrated, even if he is accused of weakness?
Or does he benefit from a more aggressive approach, with the risk of escalation that might consume his presidency?
Donald Trump, his near-certain opponent in the 2024 presidential election, has also weighed in.
Sadly, as often in America, a vital US strategic decision is mired in short-term political calculation.
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