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Who Are the Houthis and Why Are They Attacking Saudi Arabia’s Airports?

✇TIME
By: Olivia-Anne Cleary and Callum Sutherland
Supporters of the Houthis gather during a protest against Saudi intervention in Yemen, in Sanaa, on Oct. 9, 2026. —Mohammed Huwais—Getty Images

The European Union and Gulf Cooperation Council on Thursday announced the postponement of a joint summit set to take place in ‌Saudi Arabia next week, amid safety concerns prompted by Houthi attacks on airports in the kingdom.

Citing the “continued attempts by the terrorist Houthi militia to target the Kingdom of Saudi Arabia and its civilian infrastructure, which threatens the security and safety of innocent civilians,” the council said the Gulf-European Summit will be rescheduled.

The postponement comes after Yemen’s Houthi rebels on Wednesday vowed to forge ahead with the attacks on Saudi Arabia’s airports and oil facilities, just hours after striking oil giant Saudi Aramco’s headquarters.

“Operations toward Saudi depths will continue in the coming days,” said Houthi military spokesman Yahya Saree, describing the locations as “legitimate targets” and framing their attacks as a direct response to Saudi strikes on Yemen. Saudi-led forces said they had intercepted a ballistic missile fired by the Houthis towards Riyadh on Wednesday and local journalists reported hearing “loud blasts” in the Saudi capital.

The escalation follows weeks of fighting between the Iran-backed Houthis and the Saudi-backed government of Yemen, shattering a four-year informal cease-fire in the country's civil war. The conflict reignited amid the widespread fallout of the U.S.-Iran war, bringing further instability to the Gulf region. In September, the Houthis said they had captured the strategic Perim Island that sits in the Bab el-Mandeb Strait, a critical maritime chokepoint. They also seized other islands in a bid to tighten their grip on the Red Sea coastline. Amid fears that a stronger Houthi position along the coast could further constrain global energy supplies, Saudi-backed forces recaptured key areas around the strait in early October. The Houthis have since ramped up their focus on Saudi Arabia’s airports and energy infrastructure.

Tuesday night’s attack on Aramco’s executive offices in the eastern city of Dhahran caused a limited fire, Saudi’s Ministry of Energy confirmed. No injuries were reported. TIME has reached out to Aramco and the Saudi government’s media office for further information. Saudi authorities said several missiles and drones had been intercepted elsewhere, and that falling debris injured four people in the capital of Riyadh. Saudi Arabia launched strikes on an oil depot on the outskirts of Yemen’s capital Sanaa on Tuesday, as the tit-for-tat attacks escalated.

The Saudi strike on the oil depot appeared to be in response to the Houthis’ attack on King Khalid International Airport in ​Riyadh on Saturday that killed 13 people and left over 300 injured. A projectile hit that same airport on Sunday, killing one person, Saudi Arabia's General Authority of Civil Aviation (GACA) confirmed. The week before, an attack on Abha International Airport killed two people and wounded 28, said GACA.

Saudi Arabia is the world’s top purchaser of American weapons, according to the Stockholm International Peace Research Institute. However, it is struggling to defend itself against the Houthis, who are positioned to strike deep into the kingdom. The Saudis are currently investigating how their defense systems failed to stop the deadly attacks. Experts cite the vast mass of Saudi land as one reason why defensive measures may have failed. The Saudi border with Yemen stretches more than 800 miles. “Expecting a country the size of Saudi Arabia to intercept every missile is simply unrealistic. No defense can guarantee complete protection,” said Ali Shihabi, a Saudi analyst, in an online post.

Operations at King Khalid remain suspended in the wake of the attacks. Etihad Airways, Qatar Airways, and Philippine Airlines are among the carriers to announce a suspension of flights to ​Riyadh.

The U.S. embassy in Riyadh has warned Americans in the country of “potential flight cancelations, airspace closures, and travel disruptions,” stipulating that U.S. government employees now require “special authorization” to use any airport in the country.

President Donald Trump on Tuesday said the Houthis “are behaving very badly.” In a Truth Social post, he continued, “I thought they learned their lesson a year ago when we bombed the hell out of them and, at their request, stopped,” seemingly referencing the U.S. strikes between March and May last year, which came in response to the Houthis attacking vessels in the Red Sea and disrupting global trade. Weeks after the strikes began, a cease-fire between the U.S. and the Houthis was reached via Omani mediations.

On Saturday, Trump suggested that the U.S. may join Saudi strikes on the Houthis. Asked about the possibility of U.S. strikes, a senior U.S. official told TIME that Washington is “in continuous dialogue with Saudi Arabia and the Republic of Yemen Government regarding regional stability and we will always fulfill our commitments to our partners.”


As tensions in the region continue to escalate, here’s what to know about the Houthis, their history with Saudi Arabia, and why they are attacking airports.

Who are the Houthis?

The Houthis are a political and armed group in Yemen that first emerged in the 1990s and have been fighting the country’s internationally recognized government for around two decades. The group is a revivalist movement for Zaidism, a branch of Shi‘ite Islam. The Zaidi muslim population in the country represents around 35% of the Yemeni population.

The Houthi movement was largely born from a transformation of the Believing Youth Forum (BYF), according to the Carnegie Endowment for International Peace. The group became known as the Houthis in honor of their founder and leader, Hussein al-Houthi. Before he was killed by Yemeni forces in 2004, al-Houthi had developed the group into a more militarized movement. The group is now led by his brother, Abdul-Malik al-Houthi.

Civil war broke out in 2014 after the Houthis seized Sanaa, forcing the government to flee to the southern city of Aden. Since then, the group has been engaged in fighting against a Saudi-led coalition supporting Yemen’s government. The Houthis currently have control of most of the country’s west, including Sanaa. 

Experts compare the Houthis to authoritarian regimes on account of the social restrictions imposed in areas under the group’s control and alleged human rights abuses. 

“The Houthis are dominated with very ideological and radical ideas, like a Zaidi ISIS. They have similarities also with the Taliban in terms of social control," says Mahmoud Shehrah, a Yemeni political analyst at London-based think tank Chatham House. 

How are the Houthi rebels linked to Iran?

The Houthis hold strong ties to Iran, often taking action in line with Tehran’s objectives. 

“Since 2009, Iran [has] started to speed up weapons supplies, training, but also a lot of funding to the Houthis,” says Farea Al-Muslimi, a Yemeni research fellow at Chatham House, noting that links between the two began as early as the 1990s.

The Houthis are often considered part of Iran’s proxy network, known as the “Axis of Resistance,” which also includes Hezbollah in Lebanon, the Islamic Resistance network in Iraq, and previously the Assad regime in Syria, until its collapse in December 2024.

In response to the Israel-Hamas war, the Yemeni militia launched several strikes on shipping vessels in the Red Sea, disrupting global trade in late 2023 and the early months of 2024. The U.S. and U.K. joined forces in January 2024 for a series of strikes on Houthi targets across Yemen in retaliation for the attacks on unarmed vessels. The U.S. carried out an additional campaign against Houthi targets later that year.

The Houthis entered the Iran war in March by firing a barrage of ballistic missiles at southern Israel. In the months since, the group’s advances along the Red Sea are widely considered to serve the interests of Iran. A Houthi blockade in the region against Saudi Arabia was declared in July, and several vessels have been attacked. The threat that the Houthis could bring another critical maritime chokepoint to a standstill, much like Iran has done with the Strait of Hormuz, could give Tehran significant leverage in its negotiations with Washington.

However, experts say it’s not entirely accurate to call the Houthis a direct proxy.

"The Houthis are one of the more independent regional allies of Iran in the Middle East. They have their own independent interests, even though their interests converge regionally and globally,” says Fawaz Gerges, a professor of international relations at the London School of Economics.

Even so, the Houthis have become increasingly vital for Iran. “With the fall of Assad, with the weakening of Hezbollah, the Houthis became the most important regional ally Iran has,” says Al Muslimi, pointing specifically toward the Houthis' ability to disrupt trade in the Red Sea.

What do the Houthis want?

The group’s goals have changed over time, as regional developments have unfolded, experts note.

“The Houthi's ultimate goal is to be a regional power,” says Al-Muslimi. With regard to the reignited civil war, the Houthis ultimately want an end to what they call a Saudi blockade of ports and airports in their territory.

“The Houthis want to have the skies and the ports of the country open for trade, for goods and services,” says Gerges. “They want money to flow into the coffers of the Houthis.”

The civil war has had a disastrous effect on Yemen, with nearly half of the population in government-controlled areas facing high levels of acute food insecurity, according to the United Nations. “The current situation is very dire for the Yemeni population, but also for the ability of the Houthis to rule Yemen effectively,” says Gerges.

“The Houthis want to consolidate rule and regime. They want to be recognized as the legitimate government in Sanaa, as opposed to being considered a non-state actor,” he adds.

When did the Houthis and Saudi Arabia begin fighting again?

A cease-fire brokered by the United Nations in April 2022 largely held for over four years, before collapsing in July. The Houthis claimed Saudi Arabia had launched strikes on Sanaa Airport, targeting a Houthi delegation returning from Iran. In a move they framed as retaliatory, the Houthi rebels launched ballistic missiles toward Saudi Arabia. 

“The Houthis saw this as a golden opportunity to change the balance of power against Saudi Arabia and Yemen itself and launch a lightning offensive,” says Gerges.

Following further strikes on Houthi targets later that month, the militia group began striking oil refineries in Saudi Arabia, belonging to the state-owned petroleum company Aramco.

In September, strikes on oil refineries and other related facilities ramped up, and Saudi Arabia’s airports became a target.

Fighters loyal to the Houthi militant group during a rally in Sanaa, Yemen, on Sep. 10, 2026. —Mohammed Huwais—Getty Images

Why are the Houthis attacking Saudi airports?

Prior to the 2022 cease-fire, attacks on airports were largely considered a signature move of the Houthis.

In a highly-publicized attack, the group struck Abha International Airport in June 2019, injuring at least 26 people, Saudi authorities said. The strike earned international condemnation and was deemed a possible war crime by Human Rights Watch.

Now, after fatal strikes on ​Riyadh’s King Khalid International Airport, the Houthis have threatened to keep targeting airports. The main motivation behind these attacks is the economic and geopolitical pressure they apply to Saudi Arabia, experts say.

“The Houthis want to put severe pressure on the Saudi Arabia economy, airport infrastructure, and security,” says Shehrah. “They want to squeeze Saudi Arabia's arms to push them to a political settlement.”

The unrest threatens to have a strong economic and political impact on Saudi Crown Prince Mohammed Bin Salman's governance. The disruption is “costly” to him, says Al-Muslimi, who notes that Bin Salman is eager for Saudi Arabia to be seen as a “safe harbor.” 

The financial and reputational damage of these strikes has also put the Saudi public on the frontline of the conflict. It’s a “shock, because it's the first time in years that such major attacks have targeted deep inside Saudi Arabia,” says Gerges.

“The Houthis are trying to exert tremendous pressure on the leaders of Saudi Arabia to force them to accept conditions for lifting the blockade on Yemen and recognizing their legitimacy,” he continues. “Although, I doubt that the Saudi leadership will concede to Houthi demands… this would be seen as a surrender and humiliation."

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The surprisingly hopeful quest to fix concrete

✇Vox
By: Sara Herschander
High-angle view of construction workers
Concrete, one of the dirtiest substances ever concocted, could help save the planet | Aleksei Zotov/UCG/Universal Images Group via Getty Images

No, Rome was not built in a day, but it was built at breathtaking speed, its temples, amphitheaters, and aqueducts rising with the help of a magical blend of volcanic ash and lime. Today, that miraculous mortar has a less than enchanting name: concrete.

“Romans lived through a true architectural revolution, and at the foundation of this revolution, literally, was a concrete discovery,” said Admir Masic, a materials science professor at MIT who made waves a few years ago for unearthing the fast-hardening secret sauce for why Roman concrete is so durable. “They were able to take a pile of dirt and mix it together, add water, and turn it into solid rock of any arbitrary size. It literally changed everything.” 

ROME, ITALY - MARCH 30: A general picture shows the main facade of the Pantheon in Piazza della Rotonda on March 30, 2024 in Rome, Italy. Featuring 25.000 archaeological sites and locations, including some of the major and outstanding monuments of antiquity, the historic centre of Rome was declared a World Heritage Site by UNESCO in 1980. (Photo by Emanuele Cremaschi/Getty Images) Tourists visit the Colosseum area on a summer day in Rome, Italy, on July 4, 2026. (Photo by Andrea Ronchini/NurPhoto via Getty Images)

And yet, for a millennia after the fall of Rome, the world largely forgot about concrete, until, in the 18th century, an English mason found that mixing limestone and clay could form a paste that hardened underwater. Another few decades later, concrete as we now know it was reborn, and once again, it changed everything. 

In the centuries since, concrete has come to reshape our way of life, with disastrous results for the climate. What early concrete evangelists didn’t realize was that the modern way of producing the substance released giant amounts of carbon dioxide into the atmosphere. As it has become increasingly central to modernity, it has helped fuel environmental catastrophe.

Today, however, a new generation of concretophiles like Masic have pored over the poured mixture in search of another miracle, a greener, more durable kind of concrete. And they’ve found multiple answers, from concrete that can heal its own cracks — as the Pantheon has for millennia — to electroconductive concrete capable of storing energy to a blend that allows concrete to soak up more CO2 than it emits. 

Together, they suggest that in a not-so-distant future, concrete — yes, concrete — one of the dirtiest substances ever concocted, could help save the planet, transforming our built environment while actually intervening in the climate for the better. 

How concrete built (and polluted) the modern world

It’s no wonder that luminaries of the neo-concrete age, Thomas Edison among them, marveled at the stuff just as their Roman predecessors had. They saw it as a harbinger of utopia, of a world in which anything and everything — a home, an interstate highway, a water pipe, a subway system, or a grand piano — could be molded and poured for a fraction of ordinary costs. 

Thomas Alva Edison (top left) and the construction (top right) and finished view of his concrete home. (Photo by George Rinhart/Corbis via Getty Images)

“As to concrete dogs to stand warningly in the front yard and concrete cats to purr stonily under a concrete kitchen range,” the New York Times teased Edison in 1911 when he described his plans for a concrete home finished with concrete furnishings, “he made no announcement.”

The beguiled inventor’s utopian vision of a world remade by concrete would come true in more ways than he realized. Yes, it changed the way we build forever. Muddy roads and rotting wooden sidewalks gave way to smooth gray pavement, and newly cast sewer systems saved millions of lives in the deathly dirty cities of the early industrial era. Concrete, when poured over rods of steel, proved strong enough to prop up colossal skyscrapers that Julius Caesar could only have dreamed of. 

But there was a trade-off: Every time Edison fired up his trademark 150-foot kilns, scorching the limestone inside into blistering pebbles of cement clinker, he released hundreds of tons of carbon dioxide into the atmosphere. 

Yankee Stadium was built not by Babe Ruth’s swing alone, but with around 30,000 cubic yards of Edison concrete, whose creation released at least 5,400 tons of CO2, the equivalent of driving a gas-powered car 12.5 million miles, or to the moon and back more than two dozen times. But this is nothing compared with the roughly 30 billion tons of concrete the world now uses each year, enough to have turned the gluey gray goo into the second-most used material on Earth. (The first is water. Glug glug.) 

The Anthropocene has been built atop a foundation of concrete, its weight eclipsing the biomass of all living things, and its annual carbon tab responsible for up to 8 percent of global emissions, the equivalent of the entire country of India. Critically, unlike the astonishingly enduring remnants of Rome, our modern concrete decays quickly, so it must be repoured time and time again, which only makes it more environmentally catastrophic. 

But it doesn’t have to be this way, not anymore. 

“The future of concrete is to think differently, to go away from claiming that cement is bad,” Masic told me. “Our goal is to turn this around and make concrete part of the solution instead of being a problem.”

This is why we can have nice concrete

Per ton, concrete actually emits far less CO2 by volume than other materials like aluminum, steel, plastic, or glass. 

The problem is that we use so much of it, even a slightly negative footprint can quickly become enormous. But “the upside is,” said Sabbie Miller, a professor at UC Davis who focuses on sustainable concrete, “if you’re able to come up with some small change, then those small changes will also scale” in ways “that could have a huge effect on modern society and its burdens on the environment.” 

One of those solutions takes a cue from the Romans, who made concrete differently than we do today. Their once-mysterious method ensured that hulking structures like the Colosseum or the Aqua Virgo, an aqueduct built during Augustus’ reign and still in use today, could survive for millennia while New York City’s Brooklyn-Queens Expressway or the Washington Bridge crumble after just a few decades of use. 

Bumper-to-bumper traffic along the Brooklyn Queens Expressway below the Brooklyn Promenade

It’s not just that we drive cars over our concrete freeways while the Colosseum has been mostly free of even the bulkiest chariot wheels for millennia. The answer, according to Masic’s research, lies in the Romans’ ingenious recipe for cement, the glue that binds concrete together. When the ancients brewed a batch of cement, they left big white chunks of dormant lime in the final mixture. Later, if a crack formed, any water would react with the idle lime, filling the fissure with new stone. Our modern concrete has no such lime clasts, meaning that if water seeps into a crack, it degrades the structure from within, rusting the rebar that made our big towers possible, leading to a grim condition known as “concrete cancer.” 

Masic has recently turned his research into a startup called DMAT that reserves unreacted lime in concrete, giving it self-healing properties he says could extend a structure’s lifespan by about 50 percent, which in and of itself would reduce its carbon footprint by 40 percent. If the construction industry normalized such concrete or other mixtures that emit, say, half as much CO2 as usual, it would keep hundreds of millions of tons of it out of the atmosphere each year. 

But why stop there? Some startups have gotten much better in recent years at producing concrete capable of quite literally breathing in more CO2 than it emits in a process that takes advantage of concrete’s natural porousness. It could, in theory, turn our cities into concrete rainforests by turning the material into a storage reservoir. As Miller put it, “what if we can use our concrete to undo some of our environmental damages that we’ve already caused?” 

In the Bahamas, the startup Partanna has already built what it’s called the world’s first carbon net-negative home, an unassuming 1,250-square-foot abode that the company claims will sequester 182.6 tons of CO2 in its lifetime, the equivalent of hundreds of trees. Meanwhile, Masic’s lab has been piloting ways to turn concrete into a giant battery, capable of storing solar power during the day and releasing it at night, a green innovation that could cancel out its own carbon footprint within a few years of use. 

Masic believes that electroconductivity could be key to catalyzing a new era of concrete — more so even than his neo-Roman ventures. “It might hold the secret,” he said,  “for turning a bad guy into something amazing.” 

But as promising as these innovations are, it will take time for them to ripple out from model homes and into the concrete that actually surrounds us. American concrete startups have lost billions of dollars in federal funding and expected procurement contracts under the Trump administration. Some states, most notably California, are helping to pick up the slack, but investment still lags behind potential. There’s also the challenge of convincing builders running on paper thin margins that their old ways of doing things might fit better in a new mould. 

But concrete’s staggering scale means that we can’t afford to keep pouring it without considering its ugly trade-offs. More importantly, perhaps, we can’t afford to miss out on the opportunity that such a mammoth, transformative material presents to change everything yet again. 

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