Tomahawk rockets destroyed radar sites controlled by the rebels after US warships came under missile attacks twice in four days. The rebels have denied any responsibility.
The US action comes days after Saudi planes hit a funeral gathering in Yemen’s capital Sana’a kiling more than 155 people.
Just after the attack on the funeral, the US had said it would review its cooperation with Saudi Arabia but the latest strikes seem to be doing the reverse.
Some critics doubt the US strikes were justified.
“There were no missile strikes or attacks against American ships,” says Muhammad Marandi, an Americas specialist with the University of Tehran.
“Those are fabrications by the Americans because they felt the need to put extra pressure on the Houthis and the Yemeni army resisting the Saudis, since the Saudis are losing the war.”
According to Marandi, the Saudis and their allies created a naval blockade around the access ways to Yemen’s ports. But a successful Houthi attack against an Emirati vessel forced Saudi and Emirati warships to pull away from the shore, “thus allowing more food to enter the country”.
He sees the American claim that that they were attacked as was an excuse to directly enter the war.
“The Americans are basically carrying out these attacks in support of the Saudis and the Emiratis to reinforce the siege against the Yemeni people and to induce starvation as a weapon to put the Saudis in a stronger position at the negotiating table,” he says.
Legitimate or not, Saudi Arabia will be pleased with the American action, which comes just days after Washington had expressed strong doubts about its military support for Riyadh.
A bombing raid of a funeral gathering in the outskirts of Sana’a, cost the lives of more than 150 people, promting a US military spokesperson to say Washington’s support to Saudi Arabia was not “a blank check” and would be reviewed.
The Saudis were quick to announce an investigation.
“They want to see whether it was one of their planes,” says Riyad Khawaji, director of the Institute for Near East Military Analysis in Dubai. “Some said that there were no air strikes in that area of Sana'a and there were also reports that this might have been a suicide bomber."
A Saudi-led investigation into alleged Saudi war crimes is simply not credible, says Andrew Smith of the Campaign Against Arms Trade.
“We can't take it seriously at all," he comments. "Saudi Arabia has a proven contempt for human rights, is one of the most abusive regimes in the world.”
“I can't imagine that there is any chance whatsoever that it would find itself guilty of war crimes.”
Smith recalls that over the summer, Saudi carried out “a very limited investigation into their conduct throughout the bombing campaign".
"They only analysed eight of the hundreds of violations they've been accused of and found themselves innocent of all charges.”
The situation in Yemen is a vicious circle where US and UK governments are keeping up good relations with Saudi Arabia, the United Arab Emirates and their local allies, for which they pay billions of dollars, Smith says.
“For the arms industry it is good business. And the governments enjoy good relations.”
But at a price.
“What we are seeing in Yemen is the escalation of a terrible war and like all wars, the civilians are paying the price.”