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These 7 neighborhoods are competing visions of a more sustainable future.

I’m a serial cheater, emotionally, on New York City. As much as Queens is my home, one of my favorite ways to lose track of time is by going down the Zillow rabbit hole and imagining all the other lives I could live somewhere else. If I had $2 million, would I move into a houseboat to live out my Sleepless in Seattle dreams? (You laugh, but at least a floating home is floodproof!). Or maybe I’d go to California to be closer to my extended family? (Never mind — I’d never be able to afford the fire insurance).
Recently I’ve become especially captivated by “intentional communities,” of which there are thousands worldwide and hundreds in the United States alone. These are experimental master-planned neighborhoods that revolve around shared values that often pertain to things like sustainability, communal living, green spaces, and minimizing individual impact — things that might be necessary to adopt in some form on a wider scale in the coming years.
Some of these communal neighborhoods are pretty out there (think aquaponics that runs off a “VillageOS”). Others are so alluring that without even realizing it, I found myself browsing their availability pages. Oops — don’t tell New York.
Here are a few of the innovative neighborhoods that caught my eye:
Location: Utrecht, Netherlands

You’ve joked about running away to go live in the woods, but what if you didn’t have to make the choice?
Designed by Stefano Boeri of Verticle Forest fame and Roberto Meyer of the Dutch firm MVSA Architects, Wonderwoods is a 200-apartment, two-tower project in Utrecht, the fourth-biggest city in the Netherlands. The pair of structures, set to open in 2024, look in the renderings like something nature has reclaimed. But the 10,000 plants and 300 trees that will eventually cover the buildings’ balconies, roofs, and facades aren’t just there to look cool.
By decking out Wonderwoods in the equivalent of one hectare of forest, the designers aim to maximize the known benefits of urban tree planting: Plants suck up CO2, help filter out environmental pollutants, and can even generate microclimates that will be important in a warming world (the cooling effects of plants will also help reduce the energy demand of air conditioners).
Wonderwoods’ co-designer, Boeri, has been called “perhaps the most famous name in green architecture,” and he is both prolific and influential: The Dutch project is just one of the dozens of plant-coated buildings that have been, or are being, constructed around the world.
Not all of these experiments have been successful — rumor has it the Qiyi City Forest in Chengdu is overgrown and bug infested — and some scientists have downplayed the greenhouse gas-mitigating effects of so-called biophilic design. Still, if we’re to survive in a hotter, more concrete-covered world, we’ll need to bring plants along with us.
Would I live here?: I’ve always been jealous of people who junglefy their living spaces with lots and lots of plants (Hilton Carter, please decorate my home!). Tragically, I don’t always have the greenest thumb — I’m an overenthusiastic waterer — but the good news is, Wonderwoods has a team of rappelling gardeners who will maintain the exterior vegetation for you. Getting to enjoy the lushness of a rural forest in the heart of urban Europe without having to do any of the work? Count me in — I’d live here for sure.
Live, Work & Play at Wonderwoodswww.youtube.com
Location: Tempe, Arizona

Forget electric vehicles: Residents of Culdesac, a rental community just across the river from Phoenix in Tempe, Arizona, are “contractually forbidden from parking a vehicle within a quarter-mile radius of the site.”
While that might sound practically un-American to some, it’s a paradise for others. The 17-acre, $170-million project includes 761 apartments, a light rail stop (which is free with residency), communal courtyards, a coffee shop, restaurant, gym, grocery store, soon-to-open coworking space, car-share pick-up and drop-off, and, yes, visitor parking.
Culdesac isn’t the only car-free community in America, as Jalopnik reports. But while the communities tend to be popular, especially with young professionals (40% of the people on Culdesac’s opening waitlist were from outside of Arizona), “these kinds of developments often aren’t legal to build in large parts of the country due to mandatory parking minimums,” Jalopnik adds.
That doesn’t deter its founders. The long-term “vision of Culdesac,” Ryan Johnson, Culdesac’s chief executive, told The New York Times, is to eventually “build the first car-free city in the U.S.”
Would I live here?: One of the biggest deterrents against leaving New York City is being saddled with car payments — not to mention that my husband doesn’t drive. Despite being located in the heart of the Phoenix sprawl, Culdesac seems genuinely committed to making a car-free lifestyle work for its residents, offering benefits like free rides on the metro, bike parking, $5-an-hour car-sharing, complimentary Lyft Pink, and rentable Bird scooters on site. Coming from the New York real estate market, its prices also seem reasonable — available one-bedroom units start at $1,390 a month. I know because I was tempted enough to look. If only I liked the heat a little more …
Culdesac Tempe: The First Car-free Community Built From Scratch in the USwww.youtube.com
Location: Vienna, Austria

Vienna is one of the fastest-growing cities in Europe, which has created a massive demand for housing. In order to meet the demand, Vienna is building a city within a city — and taking it as an opportunity to do things right.
With over 11,000 new homes (including the world’s second-tallest timber building), the neighborhood of Aspern Seestadt is nearly net-zero, relying on technology and cutting-edge construction techniques to lower its footprint. Excess heat and electricity in one building can be sent to another, for example, while 80% of its residents reportedly travel by bike, foot, or public transit.
But what sets Aspern Seestadt apart from other green, pedestrian-friendly communities around the globe is its emphasis on centering women’s and families’ needs. For one thing, all of the streets and public spaces in the neighborhood are named after women, but the attention goes beyond the symbolic — the pavement is also wide to accommodate strollers, and ramps are included alongside staircases; parks and other gathering spaces have plentiful public toilets; pram parking and storage are readily accessible. There are also extra safety measures, like more lights in dark spaces, abundant alarms and assistance buttons, and extra guards during nighttime hours.
Buildings in Aspern Seestadt also mix housing with nurseries, shops, and coworking spaces so “women, as well as men, can … better reconcile professional and personal life,” Germany’s Gettotext.com reports. It’s a model more intentional communities should take note of.
Would I live here?: Vienna has repeatedly been cited as the city with the highest quality of life in the world although the picture might not be as rosy if you aren’t Austrian. The expat resource website InterNations lists Vienna as the “worst-rated city” in the world when it comes to the “ease of settling in” due in large part to it also being in last place for “local friendliness.” As amazing as it’d be to be integrated into a community like Aspern Seestadt — especially, eventually, as a mother — it’d probably be terribly isolating to get the cold shoulder from my new neighbors. For the “new girl in the high school” vibes this is giving me, I’d potentially pass.
Vienna is Building a $6BN "City Within a City"www.youtube.com
Location: Barcelona, Spain

One of the major criticisms of intentional communities is that they’re not actually all that “green” since they require new construction, which in turn uses up resources and adds to emissions. Additionally, many of the neighborhoods featured in this article simply aren’t scaleable to the necessary degree; 4.4 billion people live in cities and moving all of them into net-zero villages or buildings would be next to impossible.
But what if existing neighborhoods could retroactively be made greener and more habitable? That’s the radical idea behind Barcelona’s superilles, or superblocks, which began reclaiming city streets for pedestrians back in 2013. The basic idea involves cordoning off 3x3 city blocks, diverting thru-traffic around the “islands,” and limiting the roads within the blocks to six-mile-per-hour residential traffic. This transforms the interiors of the superblocks into safe places for pedestrians to walk and kids to play; the new green spaces help eliminate the urban heat island effect and boost mental health; and the walkability encourages increased foot traffic, in turn reducing emissions.
The experiment has been an enormous success: NO2 pollution has dropped 33%; noise in superblocks dipped by 9 decibels, and local businesses have seen increased sales as residents opt to shop within walking distance, a positive illustration of the urban planning concept known as the 15-minute city.
Today, there are only six superblocks in the capital of Catalonia, but the goal is to expand the concept city-wide to potentially as many as 500. In the next decade, it aims for every resident to have a public square and a green street within 650 feet of their home.
Would I live here?: Psst, New York City, can’t you take a hint? The COVID-19 pandemic gave New Yorkers a taste of what it might be like if our city prioritized the needs of pedestrians over drivers with its “open streets” program, although most of that progress has been rolled back. Barcelona is proving we could be better if only we had our priorities in the right place. Sure, it’s a sí from me when it comes to moving to Spain, but it’d be even neater if we could bring the superblock experiment back home.
Superblocks: How Barcelona is taking city streets back from carswww.youtube.com
Location: Near Amsterdam, Netherlands

“The Tesla of Eco-Villages” might not sound quite as appealing as it once did. But if you want to live minimally but aren’t quite ready to give up your Apple Watch, then ReGen Villages might be for you.
While other projects I've highlighted reimagine urban living, ReGen Villages wants to reinvent the “neighborhood development outside of cities.” The 50-acre community of 300 homes is planned for a rural region about a half-hour drive outside of Amsterdam and aims to combine vertical farming, aquaponics, renewable energy, and waste-to-resource systems to form an almost entirely self-sustaining, closed-loop community.
But this isn’t your hippie aunt’s crunchy, off-the-grid living. Conducting the complicated system will be the “Village OS” software, which eventually will use AI to “optimize living conditions, energy use, and overall efficiency,” and even potentially communicate with other future ReGen Villages around the planet, Insider reports.
ReGen Village has run into a number of roadblocks since it was first announced — construction on the complex was originally slated to begin in 2017 but it has encountered zoning, permitting, and funding problems and its website says the company is “in [the] process of raising a Series-A round of investment” to build out the operating system to test in “pilot communities.” But if the Amsterdam location doesn’t work out, stay tuned; ReGen is a California-based company and it reports interest in the concept is high in the U.S., particularly the Northeast.
Would I live here?: I’m all for off-the-grid living but something about ReGen Villages feels a little … cult-y? Maybe it’s the all-seeing AI, or the active discouragement of owning a car while living in a rural area, but something about this whole scheme sounds like the starting premise of an Ari Aster film. I’ll keep my cell reception, thanks.
ReGen Villages - Index Award 2017 Finalistwww.youtube.com
Location: Dubai, United Arab Emirates

A desert oil state might seem like an unlikely place for a sustainable city; in 2003, the United Arab Emirates had the highest ecological footprint per person of any nation (and it’s not much better now). But as part of a region-wide effort to convince the rest of the world that climate objectives are compatible with fossil fuels, the UAE is hosting COP28 and touting lofty goals like making Dubai the city with the smallest carbon footprint in the world by 2050.
The 120-acre, $354 million Sustainable City is one of the crown jewels of that ongoing effort. Constructed 18 miles in the desert outside of Dubai by Diamond Developers, which built the city’s famous marina, the Sustainable City is intended as a model net-zero neighborhood, complete with self-sufficient greenhouses and biodomes, recycled water, solar panels, and intelligent design (the villas, home to some 2,500 residents, all face north, which the developers claim cuts air conditioning usage by 40%). Cars are banned inside the compound and a shopping plaza, complete with a mosque, serves all the residents’ needs.
Critics are highly skeptical of the Sustainable City, arguing the project is an “‘island’ of specialized consumption and lifestyle … that does not actually take on the challenge of sustainability.” Supporters, on the other hand, describe it as a “living laboratory” where developers are learning in real-time how to make habitable one of the most climate-threatened places on Earth. True, the Sustainable City might not be the solution to Dubai’s problems — at worst, it might represent another instance of the UAE’s greenwashing. But if its experiment is successful, the solutions it discovers could help inform better-living for everyone.
Would I live here?: There is a reason most of the homes on this list are variations on high-density living; dense urban housing tends to be far more energy efficient. While having your own villa in the Sustainable City would be pretty sweet, it does give the impression that this is just another gated community surrounded by all the other gated communities also touting their green bona fides in Dubai. On top of the human rights violations I’d have to turn a blind eye to in order to live in the United Arab Emirates, I’m not sure the Sustainable City would be right for me.
Sustainable City | Fully Chargedwww.youtube.comSc
Location: Austin, Texas

Bringing people in closer harmony with the Earth is the goal of many sustainable communities. Whisper Valley, a 2,000-acre development in Austin, just takes it a little more literally.
At first, Whisper Valley looks like many innovative developments popping up across America: The 7,700 homes come with solar panels, Google Nest thermostats, nearby community centers, and ample public green spaces (in this case, a massive 600-acre park that doubles as flood control). But what sets the community apart is what you can’t see: Whisper Valley sits on the largest geothermal grid in the world.
Drawing on the steady temperature of the deep Earth, geothermal is gaining popularity as a means of slashing energy costs and emissions associated with heating and cooling homes. In combination with solar panels, monthly energy bills in Whisper Valley run residents only about one dollar.
But the low energy impact and savings are not the only things that make Whisper Valley a model neighborhood for the future. Because of its reliance on geothermal energy, the community had no problem staying warm when a 2021 energy surge during the deadly Texas Snowpocalypse left millions of people without heat for days. “As extreme weather gets more destructive,” Fast Company writes, geothermal solutions like that in Whisper Valley may be “a way for communities to withstand their own version of Snowpocalypse.”
Would I live here?: The suburbanite in me loves a lot about Whisper Valley — the stand-alone energy-efficient homes, the communal gathering spaces, the emphasis on healthy outdoor-oriented lifestyles, and the charging stations that come already installed in the garages. For most Americans, the development likely represents a feasible way to lower the family footprint while not compromising on many of the things we’ve come to take for granted, such as having our own space and the freedom that comes with owning a car. As far as daydreams go, Whisper Valley is perhaps a little underwhelming compared to living in a sky-forest or a luxury villa. But in terms of places that real Americans might actually be convinced to live, Whisper Valley is as exciting as it gets.
Whisper Valley - East Austin's New Zero-Energy Capable Communitywww.youtube.com
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Current conditions: A wave of summer heat is headed for the East Coast, with midweek temperatures surpassing 90 degrees Fahrenheit in Washington, D.C. • Guam and the Northern Mariana Islands are bracing for winds of up to 190 miles per hour as Super Typhoon Sinlaku bears down on the U.S. territories • At least 30 people have died in floods in Yemen, which just recorded its highest rainfall in five years.
The Trump administration is holding up some funding for grants at the National Oceanic and Atmospheric Administration, The Hill reported. On April 1, the University of Colorado put out a statement saying that a federal pause on funding had put scientists who collect data about the atmosphere “at risk for elimination” after the White House Office of Management and Budget had “not released these funds.” The university’s Cooperative Institute for Research in Environmental Sciences said that roughly 30 days before running out of funds to pay scientists, “we were informed that NOAA has put a pause on all grant actions.”
As I told you back in December, the Trump administration is also working to dismantle the National Center for Atmospheric Research in Colorado, an institution credited with many of the biggest scientific breakthroughs in our understanding of weather and climate over the past 66 years since its founding. In a post on X at the time, Russell Vought, the director of the White House’s Office of Management and Budget, called the institute “one of the largest sources of climate alarmism in the country,” and said the administration would be “breaking up” its operations.
Secretary of Energy Chris Wright is scheduled to testify Wednesday morning before the House Committee on Appropriations to defend the White House’s latest budget request for his agency. He’s not the only chieftain of a federal agency with relevance to Heatmap readers who’s coming before Congress this week.
U.S. Customs and Border Protection plans to launch the first phase of what’s called the Consolidated Administration and Processing of Entries tool in the agency’s automated commercial secure data portal to allow companies to request refunds of Trump administration tariffs the U.S. Supreme Court ruled unlawful earlier this year. Solar companies are among the thousands of American businesses that filed complaints with the U.S. Court of International Trade for refunds prior to the Supreme Court’s ruling. Those, according to Solar Power World, include American Wire Group, Canadian Solar, GameChange Solar, Fluke, Hellerman Tyton, Kinematics, JA Solar, Jinko Solar, Longi, Merlin Solar, Qcells, and Trina Solar.
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Established in early 2021, California Community Power is a quasi-governmental organization formed out of nine power providers across the Golden State. On Monday, the agency inked a series of deals with geothermal power developers to expand what’s widely considered one of the most promising clean-energy sources for California, which has some of the continent’s best hot-rock resources. XGS Energy, the Houston-based startup promising to build next-generation closed-loop geothermal systems, announced a deal to build 115 megawatts of power in the state. Zanskar, the geothermal company using AI to locate untapped conventional geothermal resources, also signed an agreement with the agency.
Zanskar in particular ranked among the most promising climate-tech startups on the U.S. market in Heatmap’s poll of experts earlier this year. The company last year announced its biggest find yet, Heatmap’s Katie Brigham reported last year. XGS, meanwhile, is drawing support from the nuclear industry, as I previously reported for Heatmap.
The developer behind a major Massachusetts offshore wind farm is suing its turbine manufacturer in a bid to keep the company from backing out of the project. By February, the Vineyard Wind project off Cape Cod had installed 60 of the project’s 62 turbines, as I reported at the time. Yet the parent company behind GE Renewables, the maker of the project’s turbines, said “it would be terminating its contracts for turbine services and maintenance at the end of April,” the Associated Press reported. GE Vernova, the parent company, says Vineyard Wind owes it $300 million already.
The war in Iran is taking a toll on Central African minerals. Miners in the Democratic Republic of the Congo are curbing output of copper and cobalt as the war cuts supplies of sulfuric acid needed for leaching minerals out of rock, Reuters reported. Mine managers are reducing cobalt production to conserve chemicals.
The deal represents one of the largest public-private partnerships in the history of the national labs.
I’ll admit, I thought I might be done covering fresh fusion startups for a while. In the U.S., at least, the number of new industry entrants has slowed, and most venture capital now flows towards more established players such as Commonwealth Fusion Systems and Helion. But in February, a startup called Inertia Enterprises made headlines with its $450 million Series A raise. It’s aiming to commercialize fusion using the physics pioneered at Lawrence Livermore National Laboratory, the only place yet to achieve scientific breakeven — the point at which a fusion reaction produces more energy than it took to initiate it.
That achievement first came in 2022 at the lab’s National Ignition Facility in Berkeley, California. On Tuesday, Inertia announced that it’s deepening its partnership with Lawrence Livermore, creating one of the largest private sector-led partnerships in the history of the national lab system. This collaboration involves three separate agreements that allow Inertia to work directly with the lab’s employees on research and development, while also giving the startup access to nearly 200 Lawrence Livermore patents covering fusion technology.
The startup’s team isn’t merely a group of enthusiasts galvanized by the national lab’s fusion milestone. Alongside Twilio’s former CEO Jeff Lawson and fusion power plant designer Mike Dunne, Inertia’s other co-founders is Annie Kritcher, a senior employee at Lawrence Livermore who has led the physics design for NIF’s fusion energy experiments since 2019.
“We’re not starting from zero,” Kritcher told me, putting it mildly. “And that was really, really important to me when I decided to co-found this company.” Or as Lawson told me after the company’s fundraise in February, “the government put 60 years and $30 billion into NIF trying to get that thing to work.”
The technical approach pursued by Lawrence Livermore — and now by Inertia — is called inertial confinement fusion. In this system, high-powered lasers are directed at a millimeter-scale pellet of fusion fuel, typically a mixture of the hydrogen isotopes deuterium and tritium. The laser energy rapidly compresses and heats the pellet to extreme temperatures and pressures, driving the nuclei to fuse and releasing enormous amounts of energy. But NIF didn’t build its system for commercial purposes. Rather, its primary mission is to support the domestic nuclear weapons stockpile by recreating the extreme conditions inside a nuclear detonation, allowing scientists to study how U.S. weapons perform without conducting explosive tests.
To translate the lab’s research into a commercially viable device, Kritcher explained, Inertia must significantly increase the lasers’ efficiency and power output, targeting a system roughly 50 times more powerful than existing lasers of its class. The startup is also working to scale production of its fusion targets to drive down costs and enable mass manufacturing.
Inertia is not the only company attempting to commercialize this general approach, however. Back in 2021, as Lawrence Livermore moved closer to its breakeven moment, the future founders of the startup Xcimer Energy were taking note. Convinced that the fundamental physics of inertial confinement had been proven, they thought, “if we’re going to do this, we have to do it now,” Xcimer's CTO, Alexander Valys, told me a few years ago. He and his co-founder quit their day jobs, and Xcimer went on to raise a $100 million Series A round in 2024. Others joined in on the hype, too — the Fusion Industry Association reports 13 fusion companies that were founded or emerged from stealth between summer 2022 and summer 2023, a record for the sector.
Kritcher told me that none are adhering as closely to NIF’s successful design as Inertia. “There are fundamental technical differences between us and the other laser approaches,” she told me, explaining that while Xcimer and others are using broadly similar methodologies to produce a hot, dense plasma, the underlying physics behind their plan diverges significantly. Xcimer, for instance, is developing a novel laser architecture that hasn’t yet been demonstrated at scale, along with a different fuel capsule design than the one validated by NIF.
Kritcher will be allowed to continue her work at the lab thanks to what the company describes as a “first-of-its-kind agreement” enabled by the 2022 CHIPS and Science Act, which allows scientists at the national labs to participate in commercialization efforts with the goal of accelerating the transfer of knowledge to the private sector.
For the fusion engineer, it’s the ultimate dream come true. She first arrived at Lawrence Livermore as a summer intern in 2004, just before her senior year at the University of Michigan, and “fell in love with the lab and the NIF project,” which was still under construction at the time. She opted to attend the University of California, Berkeley for her masters and PhD in nuclear engineering so that she could continue her work there.
“I was starstruck by the possibility of fusion energy and [it having] such a big impact on humanity, and that really kept me going for a long time,” she told me. But after the NIF facility was finally completed in 2009, it failed to achieve ignition by its initial 2012 target.
By then, Kritcher was a postdoctoral fellow, and attention at NIF began to shift toward supporting the nation’s nuclear stockpile. Fusion energy was “always in the back of my mind, driving me day to day,” she said, “but you sort of forget about it, and you lose a little bit of that excitement and spark.” Under her guidance, NIF ultimately reached that watershed moment, which has since been replicated numerous times. And when it did, "it just reopened all those old inspirational feelings and motivations and excitement and it was like a 180 turning point where we all just go, oh, fusion energy is possible again with this approach.”
Many of the lab’s employees feel similarly, she said, and this close collaboration will allow some of the nation’s foremost experts in inertial confinement to work with the startup across a range of technical capabilities, including “the laser side, the target fabrication side, the simulations team side, the code development side, our physics design side,” Kritcher enumerated.
Inertia is looking to bring its first pilot plant online in the “2030s to 2040s,” she told me. By contrast, Commonwealth Fusion Systems — the most well-capitalized company in the sector — plans to connect its first plant to the grid early next decade, while Xcimer is targeting 2035. Kritcher is unfazed, though. While she acknowledges that other companies might complete their facilities sooner, she argues that Inertia still has an upper hand given that NIF effectively serves as the startup’s demonstration plant, something no other company has built.
Not to mention that all of the sector’s projected timelines remain highly speculative. There are serious technical and economic challenges that would-be fusion energy companies will have to overcome — Inertia not excepted — and the industry’s status 10 years down the line remains anyone’s guess. What’s crystal clear, however, is that a serious new contender has entered the race.
Big questions about naval strategy and the oil economy with Cornell University’s Nicolas Mulder.
After negotiations between the United States and Iran broke down Sunday without a deal, the United States Central Command said it would “begin implementing a blockade of all maritime traffic entering and exiting Iranian ports” Monday morning.
It’s hardly like traffic through the Strait of Hormuz had been unencumbered before that. The strait has been largely closed to through traffic since the beginning of March thanks to the threat of Iranian strikes on ships going in and out of the Persian Gulf. That has remained the case even after the ceasefire deal was supposed to have opened up the waterway last week. Only a few countries have been able to get their tankers out, mostly those with close trade relationships with Iran, including China.
President Trump has been seeking to reverse that state of play and open the strait to non-Iranian traffic (e.g. oil, liquified natural gas, and fertilizer coming in and out of the Gulf states), whether by badgering European allies to help clear the strait and by having U.S. Navy ships traverse the channel to clear mines and demonstrate it’s safe to navigate. He appears to have ultimately settled on blockading the blockaders.
The president said Monday on Truth Social that 34 ships had sailed through the strait on Sunday, a number that has not been confirmed by third party sources. In the run-up to the U.S. blockade, about 10 to 12 ships were sailing through the strait per day, according to marine data service Kpler and The New York Times.
So, is the blockade an escalation of U.S. pressure on Iran? A violation of the ceasefire? A “pacific blockade” designed to pressure Iran without resorting to direct strikes? And how would it work, anyway?
I spoke with Nicolas Mulder, an assistant professor of history at Cornell University and the author of The Economic Weapon: The Rise of Sanctions as a Tool of Modern War, to try and get some of my questions answered. This interview has been condensed and edited for clarity.
Let’s start from the beginning. What is a naval blockade? And how does it different from typical naval warfare?
A naval blockade is actually interesting because it is a form of warfare that has been quite regulated for quite a long time already under international law. A lot of our modern understanding of the laws of belligerence and neutrality actually comes from blockades because they impose an important stricture on international maritime traffic. As a result, they raise all sorts of questions about who wars are fought between, and what wars mean for the civilian economies of the countries involved, and what they mean for the relationship of the belligerent states and third countries.
For most of U.S. history, the U.S. was not the blockader, but the neutral wanting to bypass blockades. The reason that the United States concretely intervened in the First World War and began to really involve itself with the power politics of Eurasia in 1917 is because it insisted on its neutral rights to trade with Britain when Germany had declared an unrestricted submarine warfare campaign that was effectively a blockade of the British Isles.
Even before that, the Union used it against the Confederacy.
In the 18th century, all the big great power wars — the Seven Years War, the various succession wars, the Napoleonic Wars — all of those involved blockades.
What I find interesting is that we have this ceasefire. We have these negotiations, which are apparently still going on. But then we also have the blockade. You seem to be arguing that blockades are a part of warfare. So, is this implying that the U.S. Navy is still potentially going to be shooting at stuff, even if there’s a so-called ceasefire?
That’s the big uncertain aspect of the current situation. We are not back into the same war that we were in last week before the ceasefire took effect. The way I would interpret this is that it’s a kind of fudge. From the perception of the Trump administration, it needs to do something to not look weak, but at the same time wants to avoid the risks of a full resumption of kinetic warfare and a massive air campaign, which they had pursued for six weeks to very mixed and disappointing effects.
The one historical parallel that I think can help us make sense of what they may be attempting to do now is the practice in the 19th century of “pacific blockade.” There were several conflicts, beginning in the 1820s with the Greek War of Independence and then through a whole bunch of Latin American wars and Asian conflicts, where European great powers would blockade small countries — not to declare war on them, but to prevent any of their ships from entering or leaving to put serious pressure on them.
What they were doing in that situation was to use wartime levels of pressure without initiating the full war because they knew that the target states were basically too weak to retaliate and did not have the naval power to contest that blockade.
How can we see this operation in Iran as part of a continuum of using these strangulation-type strategies against much weaker opponents?
One way to interpret what they’re trying to do now is to apply that Venezuela-Cuba template to Iran, and to wager that if they play this carefully, they might be able to bring real economic pressure to bear without provoking Iran into as full-scale a retaliation as it was undertaking before.
But that Venezuela-Cuba template is difficult to implement in the case of Iran for two simple reasons. One is just that Iran has, of course, shown that it has quite a lot of military capacity to retaliate with drones and missiles, and also mines and small ships and submarines. It also has the ability to widen its own maritime disruption in the region, for example by working with the Houthis to really stem the flow of traffic through the Bab-el-Mandeb Strait.
What works in the Western Hemisphere, where the United States has a really unrivaled military dominance, may not be reproducible in this strategic theater.
What does the geography tell you about the ability to impose or contest a blockade like this?
They may be doing it with multiple rings, or multiple screens — a light initial screen, and then bigger barriers of ships a bit further away, so as to not risk most of their force too close to the Iranian coastline. We saw in the early phase of the war that some carrier strike groups began to operate over time further and further away from the Iranian coast, presumably to avoid the risk of being hit with missiles and drones.
In this case, one of the questions is, what kind of resources are needed to keep that going? The U.S. did run a blockade against Iraq for most of the 1990s that was in the Persian Gulf itself, which is very narrow. Iraq’s ports are a tiny sliver of land that ends in the Persian Gulf. So that was a very small stretch of coastline.
Iran should still be manageable, but it will require a wider screen, and potentially one that really crosses the entire Arabian Sea somewhere from the southern coast of Oman, diagonally, northeastwards to Pakistan, or at least the Pakistan-Iranian border, and potentially a bit further out. And if there is also interference in the Red Sea, then the U.S. Navy is going to have to route most of disabled forces all the way around Cape of Good Hope to move that whole force into the Indian Ocean.
I think that the Red Sea contingency is quite important to how this shapes up.
CENTCOM said yesterday that this blockade is on ships going in and out of Iranian ports. I wonder if this is unique historically — both a blockade of Iran and trying to impose freedom of navigation elsewhere?
It’s interesting, right? Because indeed, there is the commitment to freedom of navigation. But then it also has been suggested that the U.S. Navy will stop all ships that have paid any toll or transit fee to the [Islamic Revolutionary Guard Corps], and that paying that toll ipso facto would make their passage illegal. For that I don’t know any good historical precedent.
The other historical precedent is probably actually the Ottoman Empire and Russia and World War I. The Ottoman Empire was bottling up Russia’s Black Sea Fleet in the Black Sea by its control over the Turkish straits, which actually imposed a really serious, long run cost on the Russian economy. It’s one of the things that really fed us in the Russian Revolution. But at the same time, the Ottoman Empire was itself being blockaded by British and French forces in the Mediterranean.
Iran is blockading [Gulf Cooperation Council] states selectively — though of course, it is allowing through some shipments. But those shipments are then going to be intercepted, presumably by the Americans. So the de facto result of it is that no one is really going to be able to leave the Gulf. And that’s kind of where I see this game theoretically ending up.
So it seems like the result of this won’t be hugely different than what things were a few weeks ago, just with fewer Iranian ships getting out.
Also ships of those countries that negotiated transit with Iran.
If you looked at the news coming out of Asia and the diplomatic communiques of a large number of Asian states that brokered bilateral arrangements with Iran — so Pakistan, India; Bangladesh had done so; China, of course — but also countries that have otherwise fairly good links with the United States — the Philippines, Malaysia, Vietnam — all of them had essentially accepted that some payment to the IRGC was now the new cost of doing business. They were so desperately in need of energy supplies for the population that they decided to enter negotiations, even if, in principle, they would prefer freedom of navigation.
The likely diplomatic contestation or diplomatic issues coming out of this blockade are also going to be related to Asia, and that’s where I would focus our attention.