The US military is trying to reassure shipping companies that a multinational force is making it safe to sail through the Red Sea and Suez Canal even though attacks from Yemen-based Houthi rebels show no sign of stopping, according to Bloomberg.

The Pentagon is “engaged with industry on a near-daily basis to gauge needs and provide reassurance that the international community is there to help with safe passage,” Air Force Lieutenant Colonel Bryon McGarry, a Defense Department spokesperson for the Middle East and Africa, said Thursday in an emailed response to questions.

So far, that’s not proving enough for most shipping lines to gamble that a drone or missile aimed at their vessels won’t be one that gets past the defenses.

“It will take a little while for shippers to get a sense about the security situation,” said Mark Cancian, a retired Marine officer and senior adviser with the Center for Strategic and International Studies in Washington. “If it turns out that the US and the coalition can maintain safe passage, then I think they’ll come back. But right now they really can’t be sure.”

Cancian said in an interview that some shippers will remain “more risk-averse than others. Ones that have connections with Israel might be more reticent.”

The Houthis, who are backed by Iran, have said they’re targeting ships linked to Israel to show support for Palestinians, though ships without direct links to Israel also have been singled out.

On Thursday, the USS Mason, a guided missile destroyer, shot down a missile and a drone over the southern Red Sea, according to US Central Command. “There was no damage to any of the 18 ships in the area or reported injuries,” Central Command said in a Thursday night post on X, the former Twitter. 

Half of the container-ship fleet that regularly transits the Red Sea and Suez Canal is avoiding the route now because of the threat of attacks, according to new industry data. Many tankers and container ships are resorting to the longer — and costlier — route around the southern tip of Africa, which may lead to higher prices for oil and a variety of consumer goods.

 A.P. Moller-Maersk A/S, the world’s No. 2 container line, said it’s preparing to resume Red Sea passages “as soon as operationally possible.” But even Maersk has cautioned that “the overall risk is not eliminated in the area,” and the company said it would “not hesitate” to re-evaluate the safety situation for its vessels and employees.

Gene Moran, a defense analyst and retired Navy captain, once commanded the USS Laboon, the destroyer that shot down four drones in the Red Sea Saturday. From his perspective, the shipping companies are still looking for the American-led coalition to do more.

“This method doesn’t appear to address the cause of the threat,” Moran said in an interview. “The Houthis are able to operate from the uncontrolled portions of Yemen. Something will need to be done about that. We seem to be moving very gingerly when the conditions seem to call for a more forceful response.”

But the Biden administration has been reluctant to take action that could turn Israel’s war against Hamas in the Gaza Strip — which began after that group’s Oct. 7 assault on Israel — into a broader regional conflict. Shipping companies may share that concern.

“If the United States were to start shooting at Houthi camps, that would arguably increase the risk, not decrease it,” Cancian said. “So I don’t think the shippers are particularly anxious to start that.”

The Pentagon has said the Red Sea security initiative it’s leading — named Operation Prosperity Guardian — brings together forces from the UK, Bahrain, Canada, France, Italy, the Netherlands, Norway, the Seychelles, Spain, Australia and Greece as well as some other nations that don’t want to be named. Yet the military hasn’t spelled out details of how it will operate. 

Major General Pat Ryder, the Pentagon press secretary, said earlier this month that the coalition will function as a “highway patrol” in the sea.

Moran said that the mixed nature of the threat, which includes potential attacks from drones, missiles and small boats, makes it more challenging to respond because not all the ships participating in the force will have the same capabilities as the US ships.

For now, the operation will continue indefinitely.

“We are not putting a timeline on this operation,” said McGarry, the Pentagon spokesperson. “We’ll stand firm with our partners in the region for as long as it takes until the threat to international shipping in these waterways has ceased.”