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By Choking the Strait of Hormuz, Iran Found America’s Weak Spot

A former US diplomat explains how Tehran is using a narrow trade lane to inflict global pain

Just over a month after the United States and Israel attacked Iran, the country has suffered severe losses. But while largely outmatched militarily, Iran has used its geography to spread the cost of war. By all but shutting down shipping across the Strait of Hormuz, it has effectively grounded global oil trade to a halt and sent markets spiralling.

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Look up this trade lane—a waterway for vessels moving through the Gulf, transporting more than 20 percent of the world’s oil and liquefied natural gas—and you’ll find it described as a “choke point.” It’s a term that Edward Fishman, an energy policy scholar and former US diplomat, knows very well.

In his 2025 book Chokepoints, Fishman argues that our globalized trading system allows countries to win wars with the stroke of a pen—and it’s something America has come to master. As an adviser at the US state department, Fishman helped to devise decades-long sanction campaigns to inflict economic pain on American enemies, like Russia, China, and Iran.

But now, America finds itself at the mercy of such a strategy. In shuttering the Strait of Hormuz to the US and most of the world, Iran has forced oil prices to skyrocket, reshuffled the world’s energy power dynamics, and prompted desperate pivots from US president Donald Trump—ranging from diplomatic off-ramps to possible invasion plans to reopen the Strait by force.

As markets reel from lack of access to this crucial trading lane, and with no end to the war in sight, I spoke with Fishman to unpack how this will all likely end and determine who’s poised to gain or lose the most. This conversation has been edited for length and clarity.

Before we discuss the situation at hand, I was wondering if you could define the term “choke points.” There are two senses of the word—the geographic choke point that we see in the Strait of Hormuz, but also the financial choke points that you mainly discuss in your book. What makes each of these potent forms of economic pressure?

Choke points are parts of the global economy where one country or a coalition of allies holds a dominant position, and there are few, if any, substitutes. These have always been fulcrums of power. Going back to the beginning of recorded history, you find that city states in ancient Greece controlling choke points often conferred them quite a bit of power. These geographic choke points—like the Bosphorus or the Strait of Hormuz—were the most salient, because we didn’t live in a hyper-globalized economy back then. We didn’t have an economy with one dominant currency or supply chains that went all the way around the globe.

These physical choke points were the essential conduits for economic warfare. You need to be able to block that choke point—either with ships or, in the case of what you’re seeing right now, in the Strait of Hormuz, with low-cost drones and missiles holding commercial vessels at risk.

In the 1990s, once the Cold War ended, and Russia and China entered the global economy, they started using the US dollar to settle cross-border transactions. We all embraced transnational supply chains that went from China, to Russia, to Vietnam, to Mexico, to the United States, to Canada. We had the emergence of these economic choke points that have very similar characteristics as the geographic ones, but they exist in financial networks and in supply chains. The US dollar is involved in 90 percent of all foreign exchange transactions. It’s effectively impossible to do business as a global firm without access to it.

What made economic choke points different was that countries can use them as weapons without deploying military force. So, the US government could cut off a foreign individual, foreign company, or even an entire foreign country from the dollar without putting a single soldier, sailor, or airman in harm’s way. It’s created a whole new kind of economic warfare.

In your book, you point to a lot of examples where, even when economic choke points are applied, military action eventually follows. Despite decades of sanctions and economic........

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