Houthi Militia in Yemen Presents a Special Challenge for U.S.

When Iranian-backed militias repeatedly targeted U.S. troops in Syria and Iraq this fall, the Biden administration struck back with force. Action was needed, officials said, to deter the groups from turning Israel’s conflict with Hamas into a wider war.

But the United States has not yet retaliated against one Iranian-backed group: the Houthis of Yemen.

In the past month alone, the Houthis have launched more than 100 attacks against commercial vessels in the Red Sea, crippling traffic there.

So why has the United States taken a different approach with the Houthis? The reasons are many.

What does the Gaza conflict have to do with the attacks in the Red Sea?

The Houthis have launched missiles and drones at vessels in the Red Sea and seized an Israeli-linked ship during more than two months of war between Israel and Hamas.

Hamas and the Houthis are both backed by Iran.

A Houthi military spokesman, Yahya Sarea, said the attacks would continue “until the Israeli aggression against our steadfast brothers in the Gaza Strip stops.”

The U.S.S. Carney, a naval guided-missile destroyer deployed to the region to deter such attacks, has been busy. On one morning last weekend, the ship shot down 14 attack drones that the Houthis had launched at ships in the Red Sea.

On Monday, the Pentagon said it was establishing a multinational naval task force to protect commercial ships in the Red Sea and the Gulf of Aden. The effort, to be known as Operation Prosperity Guardian, will include Britain, Canada, France and Bahrain — the only regional ally that has joined the effort.

While the United States has shot down drones, deployed a ship and created a task force to combat the Houthis, the one thing it has not done is strike at the militia in Yemen.

What are the Biden administration’s concerns about striking the Houthis?

The Biden administration has debated whether to hit the Houthis. The decision has been “not yet,” for a number of reasons.

For one, several administration officials said, the United States is wary of disrupting a tenuous truce between Saudi Arabia and the Houthis, who spent the bulk of the last eight years at war. Hundreds of thousands of people have died in airstrikes and fighting, as well as from disease and hunger, since the conflict began.

A truce negotiated in 2022 has largely held even without a formal agreement.

The Biden administration is also deeply concerned that the war in Gaza could escalate into a wider conflict in the region.

Striking Houthi targets in Yemen — as opposed to just shooting down attack drones — could quickly escalate into a tit-for-tat between American naval vessels and the group, and could even draw Iran further into the conflict.

Tim Lenderking, the U.S. special envoy for Yemen, recently returned from the region, where he met with partners to discuss maritime security and formalizing the Saudi-Houthi truce.

“Everybody is looking for a way to de-escalate tensions,” Mr. Lenderking said in an interview. “The idea is not to engulf the region in a wider war, but rather to use the tools available to us to encourage the Houthis to dial back their reckless behavior.”

Why has the U.S. been less hesitant to strike at militias in Iraq and Syria?

The Pentagon has said it will protect the 2,500 U.S. troops in Iraq and 900 in Syria, who mostly help local forces fight remnants of the Islamic State. Dozens have been injured in the recent militia attacks, including 25 who suffered traumatic brain injuries.

“If attacks by Iran’s proxies against U.S. forces continue, we will not hesitate to take further necessary measures to protect our people,” Defense Secretary Lloyd J. Austin III warned in October after American fighter jets struck two facilities linked to Iran’s Islamic Revolutionary Guards Corps and affiliated groups, which the Pentagon blamed for the drone and rocket attacks against U.S. forces.

None of the Houthi attacks have led to any American casualties, one official noted.

But the barrage has upended trade and prevented many ships from reaching Israeli ports. Some shipping and oil companies have been scared off and trade has been rerouted, a disruption that is expected to trigger higher prices for consumers.

So will the Biden administration take the gloves off?

Possibly, if the attacks continue, military analysts said.

“In the Navy, we have a saying: ‘You don’t shoot the arrow. You shoot the archer,’” said Robert B. Murrett, a retired Navy vice admiral and former Naval intelligence officer who was the director of the National Geospatial-Intelligence Agency. “I’m sure the strike targets have been dusted off.”

But, he said, administration officials are asking themselves, “If you do that, will it be escalatory?”