When Both Doors Close

I knew the Strait of Hormuz was important. I couldn’t have pointed to it on an unlabeled map with complete confidence, but I understood the basics.

It’s that narrow stretch of water at the mouth of the Persian Gulf. A tremendous amount of the world’s oil passes through it. Iran sits alongside it. If Iran makes it difficult or dangerous for ships to get through, oil gets more expensive. And eventually, so does gasoline.

That’s about as far as my expertise went. Then another name started appearing in the headlines:

I’ll confess something.

I had to look it up.

And when I did, my reaction wasn’t, Well, that’s an interesting bit of geography. It was:

Oh. That’s not good.

Because once you look at a map and understand what these two little stretches of water actually do, what’s happening in the Middle East becomes much easier to understand. And considerably harder to dismiss as somebody else’s problem.

Think of the Arabian Peninsula as a house with two important doors. On one side is the Strait of Hormuz. On the other is the Bab el-Mandeb Strait. Hormuz connects the Persian Gulf with the Gulf of Oman and the Arabian Sea. Before the current war, roughly one-fifth of the world’s oil passed through it.

Saudi Arabia. Iraq. Kuwait. The United Arab Emirates. Qatar. An enormous amount of the energy those countries export has to get through that neighborhood.

That’s why we’ve heard so much about Hormuz. But there’s another route. Saudi Arabia has a huge pipeline running across the country from its oil-producing regions in the east to ports on the Red Sea in the west. That’s important because if Hormuz becomes dangerous, Saudi Arabia can move some oil west instead. Problem partially solved.

Except those ships eventually have to leave the Red Sea. And that’s where Bab el-Mandeb comes in. It’s the narrow passage between Yemen and the Horn of Africa connecting the Red Sea to the Gulf of Aden and, from there, the Indian Ocean. Go north through the Red Sea and you eventually reach the Suez Canal and Europe.

Go south and you reach Bab el-Mandeb.

It’s the other door.

And something rather important happened there in September 2026.

The Houthis are the Iran-aligned armed movement that controls much of Yemen. If the name sounds familiar, it’s probably because they’ve spent years firing missiles and drones at ships in and around the Red Sea. That month, they made a dramatic advance, capturing strategic territory including the port of Mokha and Perim Island, also called Mayun. I’d never heard of that island either.

Then I looked at where it is.

It sits right in the middle of Bab el-Mandeb.

Suddenly this isn’t an obscure story about another faction taking another piece of territory in a Middle Eastern war most Americans struggle to follow. It’s an Iran-aligned armed movement dramatically strengthening its position beside one of the world’s most important shipping lanes. Approximately 12 percent of global trade and about 7 percent of global petroleum deliveries normally pass through Bab el-Mandeb. Now put the map back together.

Iran has enormous leverage around Hormuz. Iran’s Houthi allies have strengthened their position around Bab el-Mandeb.

One door on one side.

Another door on the other.

And here’s the part that matters:

The safety valve only works if the other door stays open.

That’s when I began understanding why this story matters.

Neither do I. And this is the part I really wanted to understand.

How does some armed group occupying an island thousands of miles from my house actually affect me?

The answer begins with something surprisingly mundane:

A shipping company doesn’t need someone to physically stretch a chain across Bab el-Mandeb before it changes its behavior. Imagine you own a tanker worth tens of millions of dollars.

It’s carrying tens of millions more in oil. You have a crew aboard. And somebody tells you that along your normal route there’s now a significantly greater chance of missiles, drones or attack. Your insurance company notices too. Suddenly insuring that voyage costs more. Maybe considerably more.

At some point you have a decision to make. Pay the increased insurance premium and take your chances? Or: Go another way? And the other way can be a much longer way. Instead of passing through the Red Sea and Suez Canal, vessels can sail around the southern tip of Africa.

Take out a globe sometime and trace that route.

It’s quite a detour.

More days at sea. More fuel. More crew time. More expense. Fewer trips that same ship can make in a year. And somebody eventually pays for all of that. Here’s a hint:

It usually isn’t the ship.

This is where a Middle Eastern shipping story begins creeping into an American household. Oil becomes more expensive. Diesel becomes more expensive. And diesel doesn’t just go into somebody’s pickup truck. It moves the trucks carrying groceries to the supermarket. It powers farm equipment. It moves construction machinery.

It helps move the ships carrying products across oceans. Eventually it becomes part of the cost of getting almost everything from where it’s made to where it’s sold. That doesn’t mean a Houthi standing on an island in Yemen adds 37 cents to a box of cereal tomorrow morning. Economics isn’t that simple. But transportation costs don’t disappear.

They work their way through the system.

A little here. A little there. Until eventually somebody notices that groceries cost more, shipping costs more, airfare costs more or filling the tank costs more.

And then we start arguing about inflation.

I understand the map better now.

I understand why Hormuz matters. I understand why Bab el-Mandeb matters. And I understand why trouble at both of them at the same time can matter to people who will never come within thousands of miles of either.

But learning something usually has an irritating side effect.

It gives you more questions.

I still don’t know how much control Iran actually exercises over Houthi decisions, as opposed to how much influence it has.

I don’t know how effectively the Houthis can translate control of territory around Bab el-Mandeb into control of the waterway itself.

I don’t know how long they can hold what they have taken.

And I certainly don’t know how much of the economic pain that follows will ultimately reach American consumers—or how quickly.

Those distinctions matter.

Because understanding a danger is not the same thing as exaggerating it.

So these are the questions I’m left with:

How vulnerable is the world economy when so much trade depends on a handful of narrow waterways?

How much shipping can realistically be rerouted if both Hormuz and Bab el-Mandeb become dangerous at the same time?

How much additional leverage does Iran gain when an allied armed movement controls strategically important territory around the other side of the Arabian Peninsula?

What options exist besides military escalation to keep these waterways open?

And perhaps the question that interests me most:

How many other things affecting our daily lives are happening in places we’ve never heard of, simply because we’ve never bothered to look at the map?

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When I started, Hormuz was the only door I was watching.

Now I can trace the route from the Persian Gulf, around the Arabian Peninsula, to Suez. I can see how an island most of us have never heard of can change a shipping company’s math, and how that math can end up on a grocery receipt.

That’s why I’m going to keep looking at the map.

But the question underneath all of it hasn’t moved.

Will the other door stay open?

“I don’t know.”

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First published September 13, 2026. Last updated September 13, 2026.

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