The Brief

Gross black dust on your windowsill. Sickly yellow haze that obscures the mountains. Childhood memories of recess cancelled due to smog alerts.

You know the air here is dirty. Now learn why.

Once Upon A Time

The L.A. smog story goes a little like this: on July 8, 1943, a mysterious haze descended on the city.

"People were having car accidents," Chip Jacobs, co-author of Smogtown: The Lung-Burning History of Pollution in Los Angeles, told LAist. "Mothers were wondering why their kids' eyes were watering. Police officers were spinning loopy."

What was this strange haze? Was it a gas attack? Smoke from factories? From some distant fire?

To solve the mystery, local officials formed the nation's first air quality regulator, the Los Angeles County Air Pollution Control District. They began looking into the problem and quickly learned that there were a lot of sources of air pollution in greater L.A.: people burning trash in their backyards, oil refineries, smudge pots (which are small, smoky fires used by citrus growers to keep trees warm at night), and factories.

But soon, a Caltech scientist figured out that cars and gasoline were largely to blame for the eye-watering, lung-searing haze.

A smog-shrouded view of downtown Los Angeles on October 7, 1968.

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What Do Cars Have To Do With It?

Car exhaust has two main components: hydrocarbons, from the gasoline, and nitrogen oxides, which are formed inside hot, internal combustion engines. Both are harmful in and of themselves, but when they float into the sunny, Southern California air, the sunlight bakes them into a new chemical: ozone, also known as smog.

Once scientists figured out what caused smog, the crackdown began: in 1967, a new state air quality agency, the Air Resources Board, was formed. It enacted tailpipe emissions standards for cars. It required catalytic converters on new models, cleaner gasoline and, at the gas pump, those little rubber boots that trap fumes from the nozzle. In 1984, smog checks began statewide. Other industries had to clean up, too: oil refineries, cement plants, power plants. And as California cleaned up its air, other states and the federal government followed.

L.A. has the worst ozone, or smog, in the country, according to the American Lung Association's 2021 State of the Air Report.

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Bad Now Vs. Bad Then

The air is a lot cleaner now. In 2020 , we had 157 days of unhealthy air, compared to well over 200 in the late 1980s. However, 2020 tracked the highest number of unhealthy air days since 1997, even with pandemic restrictions seeing a drop in auto travel. So when it's smoggy, it's not as smoggy as it used to be.

But Los Angeles still has the worst smog in the country, according to the American Lung Association's 2021 State of the Air report. (Again, scientists call smog "ozone." But they're the same thing).

Greater L.A. exceeded federal air quality standards for 157 days in 2020.

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Part of the problem is that it's been hot, incredibly hot. And heat speeds up the process of ozone-formation. Experts are trying to figure out whether the spate of bad air is a new trend, reversing years of steady progress.

"Is this weather, or has this become climate?" said Atwood. "We're grappling with that question basically."

What Makes Our Smog So Special?

Three reasons.

• One, there are a lot of us, and we own a lot of cars. Angelenos own 0.54 vehicles per person, compared to 0.43 in New York City. Also, we have the busiest ports in the country, which means tens of thousands of heavy-duty diesel trucks are on our roads, and they are way dirtier than cars.
• Two, the mountains that ring the L.A. Basin trap that pollution as it gets pushed eastwards by sea breezes.
• And three, our climate. Nearly three out of four days in L.A. are sunny. And the L.A. Basin frequently experiences a weather pattern where a layer of warm air will sit on top of a layer of cooler air and prevent it from dispersing. That traps pollution closer to the ground. Think of it like putting a lid on a pot.

Where's The Dirtiest Air? Where's The Cleanest?

Because the wind blows smog east, towards the mountains, the air is worst there. So places like Redlands, San Bernardino and even the tiny, mountain community of Crestline have far worse air quality than coastal cities like Long Beach or Santa Monica.

But there's another factor to consider besides smog: the raw vehicle emissions that combine to make smog can also have localized health impacts. So if you live within 500 feet of a busy road or a freeway, you're in a pollution hot spot, because that's where vehicle emissions are the most concentrated. (Use this handy map made by our friends at the LA Times to figure out how close you live to a freeway.)

Trucks on the SR 60 Freeway drive by Anna Gallegos' backyard in Mira Loma Village, California.

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In the very worst places to live, like near a freeway in San Bernardino, you will be exposed to both smog and raw vehicle emissions, said Ed Avol, the head of the Environmental Health Division at the USC Keck School of Medicine.

"It's sort of like a double whammy, so you get both the local impact of being near a roadway, and you also get the accrued accumulation of pollution that's become a regional issue," he said in an interview with KPCC/LAist in April.

What Will Breathing Dirty Air Do To Me?

When you breathe in dirty air, it triggers an inflammatory response in your body. And once that happens, a lot of bad things can happen. In the short term, air pollution can cause:

• Difficulty breathing and chest pain.
• Increased rates of asthma.
• Respiratory diseases like bronchitis and pneumonia.
• Lost school or work days.
• Doctor and hospital visits.
  

Over the long term, it's much worse. Kids who grow up breathing dirty air, whether it's from living near a freeway or in a smoggy area, or both, have weaker lungs that don't work as well.

"If they never get that maximum lung growth early in life, it looks like it's permanently lost," Avol said.

For older adults, air pollution can contribute to cognitive decline, memory loss and premature death. It can also exacerbate heart disease, diabetes, obesity and cause cancer. There's even research suggesting fetuses are harmed when their moms breathe dirty air.

"In a cynical, joking way, you could say we believe air pollution causes everything," Avol said.

Smog-making cars on March 22, 2006 in L.A.

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How Can I Protect Myself And My Family From Bad Air?

One of the most common ways people are exposed to pollution is while driving. So when you're on the freeway, be sure to keep your windows rolled up and re-circulate the air, instead of drawing it in from the outside. Changing your air filter also helps. And new cars are more tightly sealed than older cars, keeping pollution out.

If you can, try to live at least 500 away from a freeway or busy road. If you can't, using HEPA air filters has been shown to significantly reduce indoor air pollution when the air outside is dirty. Clean that black dust, which is a combination of diesel soot and rubber dust from tire wear, off your window sills.

Outside of the home, try to walk or bike on less busy streets, to limit your exposure to vehicle exhaust. When waiting for the bus, stand back from the street corner, where pollution levels soar when vehicles accelerate from a stop. And don't exercise near busy roads during rush hour, especially in the morning, or when the air is especially bad.

You can also check the air quality every day. This South Coast Air Quality Management District map will give you a good overview of air in your area. You can also check the Purple Air network, which measures particulate matter (like soot, dust and wildfire smoke), or have a low-cost air monitor installed at your home or work.

What Do We Need To Do To Make The Air Actually Clean?

It all comes down to transportation. Cars and trucks make up nearly 90 percent of the smog-forming pollution in Southern California (not to mention they are also the largest emitters of greenhouse gases in the state), and it's because they run on gasoline and diesel.

Switching to fuels with zero tailpipe emissions, like electricity and hydrogen fuel-cells, will make a huge difference, says Will Barrett, the clean air advocacy director for the American Lung Association.

Trucks drive along Interstate 80 on February 18, 2014 in Berkeley, California.

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"We need to see more focus and urgency on the conversion of the heavy duty sector to zero emission technology," he said.

But heavy duty trucks have proven tricky, so far, to electrify, because they would require a massive battery to power them over long distances while carrying heavy loads. Also, truckers would need frequent, convenient charging stations, and that infrastructure doesn't exist yet.

California regulators, ever the clean-air optimists, are throwing cash at the program. The ports of L.A. and Long Beach, for example, have a goal of shifting their entire fleet of largely diesel trucks and equipment to zero emissions technology by 2035 -- at a cost of $14 billion. If they can figure it out, all of our lungs will benefit.

This story is part of Elemental: Covering Sustainability, a multimedia collaboration between Cronkite News, Arizona PBS, KJZZ, KPCC, Rocky Mountain PBS and PBS SoCal.

Before taking his last steps on the moon, NASA astronaut Gene Cernan made sure to scratch his young daughter's initials into the lunar dust.

He had some parting thoughts for the rest of humanity, too.

"We leave as we came and, God willing, as we shall return, with peace and hope for all mankind," the Apollo 17 commander said before departing for Earth.

That was December 1972. Now, more than half a century later, NASA may be about to fulfill Cernan's wishes.

Watch the launch live stream, set to start at 12:50 p.m. ET, here.

As early as Wednesday at 6:24 p.m., an Orion capsule seated atop a 322-foot rocket will blast off from the Kennedy Space Center in Florida. If all goes according to plan, the capsule will carry four astronauts around the moon and back — sending humans the farthest they've ever been from our home planet.

The mission will be the first launch in the Artemis moon program to include a crew. It follows the uncrewed Artemis I test flight in 2022, which sent an empty Orion capsule on a three-week ride around the moon before splashing down in the Pacific Ocean.

This time, the Artemis II astronauts will first orbit Earth to check out key systems on the spacecraft, and then trace a figure-eight path around our lunar neighbor and back. The entire journey is expected to take just under 10 days.

This mission is a crucial step toward NASA's goal of once again setting foot on lunar soil, and eventually establishing a permanent lunar presence — including a moon base — with the help of international partners.

At a press briefing on Tuesday, Mark Burger, launch weather officer with the Space Force's 45th Weather Squadron, said there was an 80% chance of favorable conditions for launch day, though they were keeping a close eye on the weather.

Jeff Spaulding, senior NASA test director, is a veteran of many launches. He said that for his part, the reality that humans would soon be flying to the moon would probably set in during the final minute before ignition.

"That's when it really starts to hit home that, you know, we really got a shot at making it today," Spaulding said at the briefing. "And I know a lot of people are thinking the same thing, because you can hear a pin drop in that firing room as you count from 10 down to T-zero."

"After that, though," he said with a smile, "it may get a little bit noisier."

Copyright 2026 NPR

President Trump is set to address the nation on the Iran war at 9 p.m. Eastern time on Wednesday night, with White House press secretary Karoline Leavitt saying he would be providing "an important update," without providing further details.

On Tuesday, Trump said he expected the conflict to be over in two to three weeks, adding, "we'll be leaving very soon," and promising gas prices would then "come tumbling down."

Trump shrugged off what would happen to the blockaded Strait of Hormuz – which has cut off one fifth of the world's oil supply – saying, "we're not going to have anything to do with it." He said that it wouldn't affect the U.S. and would be something for other countries to deal with.

"They'll be able to fend for themselves," he said, having previously told European allies who have refused to enter the war to "go get your own oil!"

The assertion to wrap up the war quickly comes just days after Trump threatened to up the ante if there was no deal and Tehran didn't reopen the strait. He said he could seize Iran's oil and blow up all of their Electric Generating Plants and desalinization plants. He also said he was considering an invasion of Iran's key oil export terminal, Kharg Island.

But on Tuesday, Secretary of State Marco Rubio echoed his boss's latest comments on the war being over in a matter of weeks, saying the main goal of preventing Iran from being able to build a nuclear weapon had been achieved.

Rubio has expressed frustration in recent days over news reports accusing the administration of lacking clear objectives in Iran.

He said the objectives were: the destruction of Iran's air force, the destruction of its navy, the "severe diminishing" of its capability to launch missiles, and the destruction of its factories.

Regime change, previously touted by the administration as a goal, was not mentioned. Earlier this week Trump said he considered regime change had been achieved, despite the fact that it remains a hardline theocracy led by the son of the previous ayatollah.

Here are more updates on day 33 of the Iran war:

Fighting overnight | World leaders | Iran | American journalist kidnapped| Hegseth visits troops | Aid hold up | Peace plan

Regional Fighting overnight

The Israel Defense Forces said they hit 230 targets in Tehran while also widening an invasion into Lebanon. Meanwhile, Iran is striking back at Gulf neighbors, especially military bases used by the U.S. this week. One of those attacks injured as many as 20 U.S. service members in Saudi Arabia.

Since the war began over a month ago, 13 U.S. service members have been killed. Iran says more than 1,700 people have been killed in Iran.

People take cover in a bomb shelter as air raid sirens warn of incoming Iranian missile strikes in Bnei Brak, Israel, Wednesday, April 1, 2026.

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Also overnight Yemen's Iran-backed Houthi rebels claimed missile attacks on Israel, which the Israeli military intercepted. The Houthis have vowed an "escalation" in attacks.

Israel's emergency services reported Iranian missiles fired at central Israel had injured 14 people, including children.

At Kuwait's international airport, Iranian drones hit fuel depots, causing a huge fire, a day after a Kuwaiti oil tanker off Dubai was hit.

In Qatar on Wednesday, a missile launched by Iran hit an oil tanker leased to QatarEnergies, which said no one was injured and reported no environmental impact.

UK, Australia leaders speak

British Prime Minister Keir Starmer addressed the nation on Wednesday about how the rising cost of living caused by the conflict will affect British citizens and what his government is doing to try to mitigate that.

He repeated a previous vow that the U.K. will only take "defensive" action against Iranian attacks in the Middle East and would not get drawn into the war. He also announced his foreign secretary would organize an international summit on the Strait of Hormuz aimed at restoring freedom of navigation.

Australian Prime Minister Anthony Albanese also gave a national address on the war on Wednesday.

Earlier this week Albanese announced his government would halve the fuel tax for three months to give Australians some respite from the rising costs.

He urged Australians to use public transport and not to hoard fuel. He also warned that "the reality is, the economic shocks caused by this war will be with us for months."

'Hospitality' is over, says Iran

Ebrahim Azizi, the head of Iranian Parliament's National Security Committee, said on X in a message to Trump that the Strait of Hormuz would reopen "but not for you."

People sift through rubble in the aftermath of a drone attack on a residential building in which one civilian was killed on March 31, 2026 in eastern Tehran, Iran.

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Referring to the period since Iran's 1979 revolution, he added: "47 years of hospitality are over forever."

Iran this week approved a bill to charge vessels for crossing the vital economic waterway.

"Trump has finally achieved his dream of 'regime change' — but in the region's maritime regime!" Azizi said.

It's not just vessels that are now trapped near the Strait of Hormuz.

An estimated twenty thousand seafarers are onboard — in an active warzone — and the U.N. is trying to extricate them.

Most seafarers are from the Philippines, Bangladesh and India and some vessels are reportedly running low on food and water.

The U.N.'s International Maritime Organization is negotiating with all sides to try to evacuate them.

American journalist kidnapped in Iraq

American freelance reporter Shelly Kittleson was kidnapped in Baghdad Tuesday, according to Al-Monitor, a Middle Eastern news site for which she has written.

Iraqi security forces said they intercepted a vehicle that crashed and arrested one of the suspected kidnappers, but are still searching for the kidnapped journalist and other suspects.

U.S. officials say they're working to get her released.

"The State Department previously fulfilled our duty to warn this individual of threats against them and we will continue to coordinate with the FBI to ensure their release as quickly as possible," Dylan Johnson, the assistant secretary of state for global public affairs, said on social media.

He said Americans, including media workers, have been advised not to travel to Iraq and should leave the country. The statement did not condemn the kidnapping or express concern.

Johnson said Iraqi authorities apprehended a suspect associated with Iran-backed Iraqi militia Kataib Hezbollah, believed to be involved in the kidnapping.

Press freedom organizations expressed deep concern. The Committee to Protect Journalists called on "Iraqi authorities to do everything in their power to locate Shelley Kittleson, ensure her immediate and safe release, and hold those responsible to account."

Based in Rome, Kittleson has reported on Iraq, as well as Syria and Afghanistan, for years, according to Al-Monitor.

Reporters Without Borders said she is "very familiar with Iraq, where she stays for extended periods."

"RSF stands alongside her loved ones and colleagues during this painful wait," the organization said.

Al-Monitor said in a statement it is "deeply alarmed" by her kidnapping. "We stand by her vital reporting from the region and call for her swift return to continue her important work," it said.

U.S. defense secretary visits troops

U.S. Defense Secretary Pete Hegseth made an undisclosed trip to the Middle East to visit troops on military bases over the weekend. He did not divulge the location for the troops' safety.

Defense Secretary Pete Hegseth speaks to members of the media during a press briefing at the Pentagon in Washington, Tuesday, March 31, 2026.

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"I spoke to Air Force and Navy pilots on the flight line who every day both deliver bombs deep into Iran, but also shoot down drones defending their base. Many had just returned from the skies of Iran and Tehran," he told reporters in a briefing Tuesday.

He said he "witnessed an urgency to finish the job" and tried to draw a comparison with America's earlier drawn-out wars in Iraq and Afghanistan.

He said the U.S. is improving bunkers and layered air defenses as a priority to protect troops and aircraft.

This comes after more than a dozen U.S. service members were injured, several severely, and U.S. aircraft were damaged in Iranian strikes on a base in Saudi Arabia last Friday. The Pentagon says 13 U.S. service members have been killed and 300 wounded in what it calls Operation Epic Fury.

He repeated the administration's assertion that the U.S. is negotiating with Iran, despite Iranian officials' denial that talks are happening.

Aid hold up

The World Food Program says tens of thousands of tons of food aid are stuck in ports as a consequence of the U.S.-Israeli war on Iran.

The WFP says there is a whole disruption in the global supply chain with carriers not able to use the Strait of Hormuz and choosing not to use the Suez Canal through Egypt out of concerns of attacks there, too.

The agency says this is adding a month to shipping time and costing more because of spikes in fuel prices from the war. It noted that as people around the world pay more for fuel, more families will struggle to put food on the table.

Some 45 million additional people will fall into acute hunger around the world if current conditions continue through June- reaching 363 million globally, the WFP said.

Pakistan, China release statement

Pakistan's and China's foreign ministers issued a joint statement on Tuesday calling for talks to the war on Iran as part of a broader peace plan. The statement called for a halt to fire, an end to attacks on civilian infrastructure, and reopening of the State of Hormuz.

For days Pakistani officials had said they hope to help mediate talks to end a war that has seized up the global economy, pushed up the price of fossil fuels, and key commodities like fertilizer — and that has killed thousands of people, mostly Iranians and Lebanese.

The joint statement with China came after high-ranking Pakistani officials led a flurry of meetings with regional powers. China is Iran's biggest customer for oil — and it's seen as sympathetic to the country.

Jane Arraf in Amman, Jordan, Diaa Hadid in Mumbai, Quil Lawrence in New York, Giles Snyder, Michele Kelemen in Washington, Emily Feng in Van, Turkey, Aya Batrawy in Dubai, and Kate Bartlett in Johannesburg contributed to reporting.
Copyright 2026 NPR

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The Supreme Court chamber will be packed on Wednesday, as the justices hear arguments in a case that almost certainly will result in a historic ruling. At issue is President Trump's challenge to a constitutional provision that has long been interpreted to guarantee American citizenship to every child born in the United States.

Listen to arguments and live NPR special coverage beginning at 10 a.m. ET:

Trump has long maintained that the Constitution does not guarantee birthright citizenship. So, on Day 1 of his second term, he issued an executive order barring automatic citizenship for any baby born in the U.S. whose parents entered the country illegally or who were here legally, but on a temporary, or even a long-term visa.

"We are the only country in the world that does this with birthright," Trump said as he signed the executive order. "And it's absolutely ridiculous."

That actually is not true. There are nearly 33 countries, mainly in North and South America, that have birthright citizenship — including, among others, Canada, Mexico, Brazil and Argentina.

Can't see the video above? Watch it here.

D-Day for Trump's attack on birthright citizenship

But Trump has long been determined to rid this country of its longstanding protection for birthright citizenship. Wednesday is D-Day in that effort, and to understand the issues, it's worth taking a stroll through American history.

While citizenship was not defined at the nation's founding, the colonists were largely pro-immigrant, according to University of Virginia law professor Amanda Frost, author of American Birthright: How the Citizenship Clause made America American, due out in September.

The founders "wanted to populate this mostly empty continent," she observes, adding that, in fact, one of the complaints against the British king in the Declaration of Independence was that the British "were discouraging immigration."

Indeed, she notes, after the Revolutionary War, even those who had been loyal to the king but wanted to stay in America were granted U.S. citizenship.

Trump's view of the 14th Amendment

Birthright citizenship didn't make it into the Constitution, though, until after the Civil War, when the nation enacted the 14th Amendment to reverse the Supreme Court's infamous Dred Scott decision — a ruling that in 1857 declared that Black people, enslaved or free, could not be citizens of the United States.

To undo that decision, the post-Civil War Congress passed a constitutional amendment that defines citizenship in broad terms. It says, "All persons born or naturalized in the United States and subject to the jurisdiction thereof, are citizens of the United States."

President Trump, however, maintains that the constitutional amendment was intended to be more limited than it has been in practice. "This was meant for the slaves … for the children of slaves," Trump said last January. "I'm in favor of that. But it wasn't meant for the entire world to occupy the United States." 

But as the University of Virginia's Frost notes, the framers of the 14th Amendment had more than one explicit purpose. They wanted a clear, bright line definition of citizenship; they wanted the former slaves and their children to be citizens, and they wanted to include immigrants, many of whom were the targets of great hostility.

"I like to remind my students that between 1845 and 1855, approximately 2 million people from Ireland fled to the United States," Frost observes. They were fleeing from famine and harsh British rule. And while "there certainly was some prejudice and discrimination and xenophobia," she says, "their children soon would automatically become American citizens" when born on U.S. soil after enactment of the 14th Amendment.

Trump's interpretation of the 14th Amendment is avowedly far more restricted. What's more, it has not been embraced by the courts or the legal norms of the country for 160 years.

The counterargument

"The president's executive order is attempting a radical rewriting of that 14th Amendment guarantee to all of us," says Cecillia Wang, legal director of the American Civil Liberties Union.

Indeed, even as both Republican and Democratic administrations have sought in modern times to deport large numbers of individuals who have entered the country illegally, the notion of birthright citizenship has remained so entrenched that during World War II when Japanese citizens were held as enemy aliens in U.S. detention camps, their newborn children were automatically granted American citizenship because they were born on U.S. soil. And Congress later codified that understanding in the 1940s, '50s and '60s.

At the Supreme Court on Wednesday, the justices are likely to focus on some of the key court decisions that have protected birthright citizenship during the past century and a half. Perhaps most important among these is the case of Wong Kim Ark, born in San Francisco in 1873 to Chinese immigrants who ran a small business in the city. Back then, immigrants like Wong's parents were largely free to enter the U.S. without any documentation, but his parents eventually returned to China. And after their son visited them in 1895, officers at the port in San Francisco refused to allow him back into the United States, contending that he was not a qualified citizen.

Wong challenged the denial and, in 1898, the Supreme Court ruled in his favor. By a 6-2 vote, the justices interpreted the words "subject to the jurisdiction thereof" to mean that all children born in the U.S. were automatically granted citizenship. The court noted that only three exceptions were specified in the amendment: The children of diplomats were not deemed to be U.S. citizens because their allegiance was to another country; the children of occupying armies were similarly excepted, as were the children of Native American tribes. Of these three exceptions, the only one that still applies is to the children of diplomats, as there are no invading armies, and Native Americans were granted automatic citizenship in 1924.

The Trump administration, however, argues that Wong Kim Ark's situation was very different from many of the children who become automatic American citizens today, because Wong's parents, though undocumented, were here legally, by virtue of having a permanent residence in the U.S. And the Trump administration points to language in the 1898 Supreme Court opinion that assumes the parents had legal status in the country because they had a permanent residence in San Francisco.

The Trump administration makes an even broader argument. "An individual who is naturally born in the United States is only considered a citizen if their parents have allegiance to the nation," says Daniel Epstein, vice president of America First Legal, the organization founded by the architect of Trump's immigration policies, Stephen Miller, White House deputy chief of staff. "It is a misdemeanor to come into the United States without authorization. That is a crime," he says. "That is strong evidence that you don't kind of meet the traditional notion of allegiance."

"We do not punish children for the sins of their parents"

Countering that argument, the ACLU's Wang will tell the Supreme Court that the men who wrote the 14th Amendment deliberately chose to confer automatic citizenship on the child, not the parent.

"And the idea — that actually goes back to the founding — is that in America we do not punish children for the sins of their fathers, but instead we wipe the slate clean. When you're born in this country, we're all Americans, all the same," Wang says.

Texas Sen. Ted Cruz is supporting the president's position, along with 11 other GOP senators, and 16 House members, who signed on to the America First brief.

"As a policy matter, birthright citizenship is stupid," Cruz says, "because it incentivizes illegal immigration. It makes absolutely no sense that someone breaks the law and they get rewarded with a very, very, precious gift, which is American citizenship."

Can an executive order trump a constitutional amendment?

The ACLU's Wang counters that Trump is trying, by executive order, to change the meaning of the 14th Amendment to the Constitution, a measure that was approved overwhelmingly by the Congress in 1866 and, after a great public debate, ratified by more than three-quarters of the states. She argues that the consequences of such a dramatic change by executive fiat would have untold consequences.

"What will immediately happen is that every month, tens of thousands of U.S.-born babies will be stripped of their citizenship. They may be stateless because their parents' country of nationality may not consider them to be citizens. And so you'll see a permanent underclass of people who have no nationality, who are living in the United States, who can't pass on their nationality to their children born in the U.S.

In a separate brief, the U.S. Conference of Catholic Bishops stresses the problems that would be created by generation after generation of children who are stateless, with no country to call home, and no citizenship to pass on to their children.

"The children … would be the ones to bear the brunt of this," says Bishop Daniel Flores, vice president of the bishops conference. "I have people asking this now in my diocese. 'Bishop, am I going to get into trouble if I give food to somebody that I'm not sure of their documentation? … Can we help these people? Because we think we need to, because they're people and they were born here."

The Trump administration counters that birthright citizenship raises two other problems: a generic potential threat to national security and the problem of so-called "birth tourism."

In fact, even birthright defenders concede that a cottage industry has long existed in which women pay money to come to the U.S. and have their children here. But the numbers are consistently very small. Even the Center for Immigration Studies, a think tank that favors limited immigration, estimates only 20,000 to 26,000 birth tourism children are born in the U.S. each year, compared to the overall birth count of 3.6 million babies born each year.

Daniel Epstein of America First Legal contends that numbers are not important. "I view just one illegal act as illegal, and birth tourism is illegal and it's against the law, and the law matters."

Population experts say that if automatic birthright citizenship were to be voided, the consequences would be profound — and counterintuitive. The Population Research Institute at Penn State, for instance, estimates that a repeal of birthright citizenship would result in 2.7 million more people living here illegally by 2045, people who previously would have been entitled to birthright citizenship, but now have no such citizenship for themselves or to pass on to their children or the generations thereafter.

Also likely to come up at today's Supreme Court argument are practical questions, like those raised by Justice Brett Kavanaugh last year in a related case. How would a hospital know that the parents of a child are illegally in the country? What would hospitals do with a newborn? What would states do? The answer from Trump's solicitor general, D. John Sauer, was "Federal officials will have to figure that out."

Copyright 2026 NPR

With the exception of a stray morning shower here and there, Southern California is in for a dry and sunny afternoon.

The afternoon sun will warm up the area a few degrees today. For the coasts, we're looking at highs around 67 degrees and up to the low 70s for the inland coast.

The valleys will see similar temperatures with highs from 68 to 74 degrees. The Inland Empire, meanwhile, will be cooler with highs around 63 degrees.

In Coachella Valley, temps will reach 81 to 86 degrees.

A wind advisory still is in effect for the San Bernardino, Riverside County mountains, including Coachella Valley, until 11 p.m. Thursday. The Antelope Valley will see some gusty winds later this afternoon as well.