While he can’t turn water into wine, Nigel Braun is making vodka out of thin air.

He is neither miracle worker nor magician. His secret is chemistry, and he films his experiments inside a commercial-grade laboratory in Montreal and shares the videos on his YouTube channel. That’s where 6.5 million subscribers know him as NileRed, like the fluorescent chemical dye, a name he acknowledges sounds vaguely biblical.

Mr. Braun’s videos surged in popularity during the pandemic, reaching 2.5 billion views, and as his audience ballooned, so did his ambitions. His experiments — often whimsical, sometimes practical and occasionally dangerous — range from transforming paint thinner into cherry cola, to developing bulletproof wood, to making carcinogens from scratch.

Over the past decade, since dropping out of grad school, Mr. Braun, 32, has outgrown a hobby workshop in his parents’ garage and two other facilities, settling into a third lab large enough to rival some academic research spaces in Canada.

But Mr. Braun considers himself less a chemist or a science communicator in the vein of Bill Nye and MythBusters than an adventurer. “I want to have a journey,” he said. “I’m not interested in just conveying information.”

Part of his appeal is that he doesn’t care to make chemistry look easy or neat.

Some of the tasks he sets himself on are both epic and arduous, like his many attempts to make purple gold, an alloy of gold and aluminum that gives the metal a unique color, but whose recipe is only vaguely described in one line of ingredients in a patent.

With no other information to draw on, the process to make purple gold was riddled with trial and error and was one of the most frustrating projects he has ever worked on, Mr. Braun told his viewers in a December 2023 video. But he ultimately succeeded, making a ring. It is probably one of the few pieces made entirely of purple gold to exist, he said, because the metal is as brittle as glass.

“Doing the science allows you to have something that you literally can’t buy,” he said, seated in his lab, where a display case holds a selection of the items he has made, including a knife beautified by bismuth crystals, a bouncy metal known as metallic glass and an ultra lightweight material, aerogel, used in space research.

The NileRed videos defy the conventional wisdom of staying relevant online by keeping it short. Mr. Braun’s latest videos tend to be about an hour long, and he publishes them infrequently — violating another rule of social media success — because of the extended timeline on his complicated undertakings.

But the lab is buzzing year-round. Thanks to the advertising and other income he brings in across all of his social media platforms — with 18 million followers and subscribers in total — his company makes a couple million Canadian dollars a year. He has hired two friends and two family members to help.

Mr. Braun’s lab is full of premium equipment and NileRed branded beakers, a far cry from his early days when he scavenged the broken glassware bin in the lab at McGill University for supplies he could repurpose.

A large container that creates an inert atmosphere for testing substances is rigged with cameras. An isostatic press can crush objects with a force like the ocean depths. He recently acquired a type of magnetic press so enormous it caused a forklift to tip.

Mr. Braun likes to use all of this top-end equipment to design experiments that take unexpected twists.

After reading an article about reducing global warming by transforming carbon dioxide into biofuels, he realized that by pulling CO2 and water from the air — and then using the water to make hydrogen — he had the basic ingredients to make ethanol, like the alcohol found in vodka.

An office joke about getting drunk on global warming birthed a vodka-from-air experiment that now occupies a lab bench covered in a maze of tubing, machines, tanks and pressure gauges. For those whose taste in alcohol runs elsewhere, Mr. Braun has also made toilet paper moonshine.

One danger of hobby chemistry — especially in a post-“Breaking Bad” world — is being suspected of using one’s powers for criminal pursuits.

Distilling alcohol for research is legal in Quebec, and Mr. Braun has so far received only one call from the Canadian police. They contacted him after his purchase of a large filter — sometimes used to make illegal drugs — was flagged by customs. But his scientific explanation put the officer at ease.

Still, sometimes he knowingly makes his experiments sound vaguely sketchy.

“Today, I’ve decided to make some fresh, powdered ‘coke,’” Mr. Braun said into the camera on a recent shoot.

After reeling in viewers with a hint that some cocaine production might be in the offing, he eventually revealed that the white powder he had in mind would be produced from the bottle of Coca-Cola he had kept concealed in a back pocket. The Coke was from Mexico, where the drink is made not with high-fructose corn syrup as it is in the United States, but with cane sugar — which is what his experiment would extract.

Based on stories he has heard from peers in the United States, Mr. Braun is not confident that all NileRed experiments would be strictly legal there. It’s one other reason he doesn’t want to relocate south of the border, despite the pull Hollywood has on YouTube stars who strike it big.

But an even more important draw to staying in Montreal: his family. Mr. Braun’s younger brother, Corey, helps manage the channel and his mother, Jody Tanaka, assists with administration. Dorian Braun, his father, helped get him started by yielding some garage space to provide the original backdrop of NileRed videos.

“It was an open workshop,” said the elder Mr. Braun, a sound engineer and retired college professor. “That means that every knucklehead kid on the street is over here, making bows and arrows and contraptions.”

When experiments went wrong — the tear gas incident comes to mind, to say nothing of the time acid vapors ate into some metal tools or the (minor) lithium explosion — the father would let out an exasperated sigh, but generally not stifle his son’s creativity.

The younger Mr. Braun majored in biochemistry during his bachelor’s studies at McGill, but he abandoned his graduate degree and his work as a lab technician after having a sudden realization about his life’s path.

“I remember this moment that hit me: Why am I doing chemistry for someone else all day when I could just do chemistry for myself?” he said.

In contrast to the protracted gaps between check-ins with his academic supervisor as a grad student, the gratification and feedback from Mr. Braun’s audience is almost immediate when he posts a video.

“I try to watch it as soon as humanly possible,” said Chenxin Li, a NileRed subscriber and molecular biology research scientist who has faced the challenge of keeping his students at the University of Georgia engaged in science.

“His channel has the perfect answer: It’s the sense of curiosity or a sense of wonder,” Mr. Li said. “That is important, especially if you run a YouTube channel, because the world’s most entertaining content is a few clicks away.”

As a scientist, Manfred Ehresmann, a space systems researcher at the University of Stuttgart in Germany, envies Mr. Braun’s freedom to take his curiosity in any direction, unencumbered by bureaucracy or the need of writing grant applications.

“If you see someone like NileRed doing it by himself, it’s a kind of inspiration,” Mr. Ehresmann said.

In future videos, Mr. Braun wants to focus on innovative materials, perhaps with an application in the burgeoning space economy.

“Science is only interesting because it’s useful,” Mr. Braun said. “If it’s not useful, it’s just a bunch of party tricks.”

An Israeli airstrike hit a factory in a small town in southern Lebanon, killing at least 10 civilians, Lebanese officials said on Saturday, as people across the Middle East uneasily awaited reprisals against Israel by Iran and its allies for a pair of assassinations.

Israel’s military said it had targeted a weapons warehouse in the area used by Hezbollah, the Iran-backed Lebanese militant group, in the strike overnight on Friday. But the mayor of the town, of Toul, where the attack took place, denied the claim.

The strike appeared to have destroyed the factory and an adjacent structure inhabited by Syrian refugees who worked there and their families. Reporters who visited the site saw steel beams but no signs of weaponry.

The mayor of Toul, Saeed Mahmoud, said in a phone interview that the factory was used to collect steel spare parts.

The death toll was one of the largest so far in Lebanon amid the near-daily exchange of border attacks with Israel in the 10 months since the war in Gaza began. Hezbollah and other Iran-backed militants have been attacking Israel in solidarity with the Palestinians in Gaza, leading to months of cross-border fire by both sides.

The tensions have escalated sharply in recent weeks following the killings of Fuad Shukr, a senior commander in Hezbollah, and Ismail Haniyeh, a top leader of Hamas, groups allied with Iran. Hezbollah and Iran have vowed to retaliate more forcefully than before against Israel, leaving the Middle East on tenterhooks for more than two weeks, awaiting the reprisals.

The Biden administration has led a diplomatic push this past week for a Gaza cease-fire, which U.S. and regional officials hope would prompt Iran and its allies to curb any retaliation and avert a wider regional war. Secretary of State Antony J. Blinken is scheduled to travel to Israel on Saturday to help facilitate the talks, which are being mediated by the United States, Egypt and Qatar.

All of the people killed in the strike on Toul, near the southern city of Nabatiye, were Syrian refugees and included a woman and her two children, said the Lebanese health minister, Dr. Firass Abiad.

More than a million Syrian refugees fled to Lebanon to escape a long-running civil war at home that began in 2011. Syrian laborers often live with their families where they work.

On Saturday afternoon, Israeli drones circled above the remnants of the destroyed factory. Next door, a collapsed concrete building held what appeared to be the sleeping quarters of the workers and their families. The broken concrete and the metal rebar that once supported the structure were strewed with clothing and the broken plastic of a child’s car seat.

One laborer was killed where he was sleeping along with his wife and two children, according to rescue workers who dug them out of the rubble. At least six other laborers were killed in the strike and two were wounded, the rescue workers said.

The Israeli military said it was looking into the claim that civilians were harmed in the attack.

Hezbollah’s chief, Hassan Nasrallah, threatened in July to hit new targets in Israel if it continued to target civilians in Lebanon. In response to the latest attack, Hezbollah said it fired a barrage of rockets at Ayelet Hashachar, a kibbutz in northern Israel.

The Israeli military said roughly 55 rockets crossed into Israeli territory, some of which ignited fires. There were no immediate reports of casualties. An Israeli soldier was severely wounded in a separate rocket attack from Lebanon on Saturday morning, the military said.

For months, Israel and Lebanon have appeared to carefully calibrate their attacks in an attempt to avoid a wider escalation.

Hezbollah has fired thousands of rockets and drones at northern Israel in solidarity with Hamas, which led the massive surprise attack on Israel on Oct. 7 that set off the war in Gaza.

Israel has responded to attacks from Lebanon with bombardments that have killed more than 500 people, most of them Hezbollah fighters, according to figures from the Lebanese health ministry, Hezbollah and the United Nations.

But after a rocket attack from Lebanon in late July that killed 12 children and teenagers in the Israeli-controlled Golan Heights, Israel killed Mr. Shukr, one of Hezbollah’s highest-ranking military commanders, in an apartment in the southern suburbs of Beirut.

Hours later, an explosion widely attributed to Israel killed Mr. Haniyeh, the leader of Hamas’s political bureau, who was staying in a closely guarded state guesthouse in the Iranian capital, Tehran, to attend the inauguration of a new Iranian president. Israel never publicly confirmed its involvement.

Iran and its ally Hezbollah have pledged to avenge the killings. But U.S., Iranian and Israeli officials said on Friday that Iran had decided to delay any reprisals against Israel to allow mediators to continue working toward a cease-fire in Gaza.

High-level talks in Qatar on a truce and the release of the 115 hostages still held by Hamas and its allies in Gaza ended without an immediate breakthrough on Friday. But the United States, Egypt and Qatar said the negotiations would go on next week in Cairo, as mediators raced to try to secure a deal.

Even as senior officials have shuttled from capital to capital in an attempt to end the war, the fighting in Gaza has gone on. Israeli aircraft struck dozens of sites across the Gaza Strip over the past 24 hours, the Israeli military said on Saturday, and ground troops swept through parts of the southern city of Khan Younis, already devastated in an earlier assault.

The Israeli military again ordered Palestinians to flee parts of central Gaza that Israel had previously designated a “humanitarian zone” for many of the nearly two million Gazans who have been displaced during the war.

Avichay Adraee, an Israeli military spokesman, said Hamas and other militant groups had repeatedly fired rockets from the area.

Many Gazans have been displaced multiple times by the war. Aid groups say there is still nowhere safe for them to go, as Israel has vowed to target Hamas wherever it believes the organization is operating.

“Many of the thousands of families affected only recently arrived in the area, after other displacement orders in Khan Younis,” said Louise Wateridge, a spokeswoman for the U.N. agency that aids Palestinian refugees.

Gazans are “trapped in an endless nightmare,” she said.

Hwaida Saad, Victoria Kim and Raja Abdulrahim contributed reporting.

Ever since the Korean War was halted in an uneasy truce in 1953, South Koreans have lived under an American promise to defend their country, if necessary, with nuclear weapons. President Biden emphatically reiterated that commitment last year, vowing that any nuclear attack by North Korea would lead to the destruction of its government.

But decades of American assurances have failed to deter North Korea from building a nuclear arsenal and then expanding it. Led by Kim Jong-un, North Korea has also become more provocative, testing missiles powerful enough to reach the United States. And it has rattled South Korea by reviving a Cold War-era defense agreement with Russia, another nuclear-armed state.

The South has long considered it a taboo to pursue atomic weapons in defiance of Washington’s nonproliferation policy. But jitters about security here have been intensified by the possible re-election of former President Donald J. Trump, whose commitment to the alliance between Washington and Seoul appears to be shaky at best.

Now, a growing majority of South Koreans say their country needs its own nuclear weapons instead of relying on the United States for protection. The idea, although still disavowed by the South Korean government, is increasingly becoming part of mainstream political debate.

Polls show that many South Koreans say they can no longer trust the American nuclear umbrella to guard them from North Korea. They doubt that Washington would come to their aid in the event of a conflict with North Korea now that Pyongyang is racing to develop the ability to attack American cities with nuclear warheads.

“We cannot expect — and should not ask — the American president to use his nuclear weapons to defend an ally at the risk of sacrificing his own people,” said Cheong Seong-chang, who leads a group of 50 analysts pushing for a domestic nuclear arsenal in South Korea. “We must defend ourselves with our own.”

South Korea abandoned its nuclear weapons program in the 1970s, as Washington pushed nonproliferation, and chose to rely on the United States to defend it against the North. Tens of thousands of American troops have been garrisoned for decades in the South, which for many years also hosted U.S. nuclear weapons. Washington withdrew those arms in 1991, hoping the disarmament would incentivize Pyongyang to stop pursuing its own nuclear weapons.

For a while, Washington had two important partners in that effort: China and Russia. But in recent years, it has found itself increasingly at odds with both of those countries on issues such as trade tariffs and the war in Ukraine. Now, neither cooperates in American-led efforts to roll back North Korea’s nuclear ambitions.

Mr. Kim’s regime has tested both atomic weapons and intercontinental ballistic missiles. It is developing technology to deliver multiple nuclear warheads with a single missile. It is also escalating its threat to target South Korea with a fleet of nuclear-capable, short-range ballistic missiles, which Mr. Kim said this month he would deploy near the border with South Korea.

In June, the Stockholm International Peace Research Institute estimated that North Korea had built roughly 50 nuclear warheads and had enough fissile material to build another 40 or so. It was also focusing on tactical nuclear weapons, which have a smaller payload.

“There is a growing concern that North Korea might intend to use these weapons very early in a conflict,” wrote Matt Korda, a researcher at the institute.

It was fears such as these that President Yoon Suk Yeol of South Korea tried to address when he met Mr. Biden at the White House last year. The two leaders deepened their alliance and signed the Washington Declaration to show that the American defense commitment was ironclad. Last month, they reaffirmed that any nuclear attack by North Korea would be met with “a swift, overwhelming and decisive response.”

“For the first time, it has been written down in a document that American nuclear assets will be tasked with deterring and countering North Korea’s nuclear force,” said Kim Tae-hyo, Mr. Yoon’s deputy national security adviser.

But that has done little to tamp down misgivings in South Korea about the American nuclear umbrella, which also covers Japan.

A poll in February showed that the percentage of respondents who said Washington would defend their country with nuclear weapons even though North Korea could attack the mainland United States with nuclear missiles had dropped to 39 percent from 51 percent last year. Another survey, which has been conducted annually for a decade, found a historical shift. Asked to choose between having nuclear weapons or U.S. troops on their soil, more South Koreans, for the first time, picked the former.

Other surveys have found as many as 70 percent of all South Koreans supporting an independent nuclear arsenal. It has become increasingly common for conservative politicians and private and government analysts to support or discuss the idea, especially after Russia’s invasion of Ukraine highlighted the extent to which a nuclear-armed power could get away with invading a nonnuclear neighbor.

“The call for nuclear weapons will be anything but short-lived because ‘going nuclear’ sounds sexy as a slogan,” said Lee Byong-chul, who has studied nuclear nonproliferation at the Institute for Far Eastern Studies in Seoul. “But there is a huge gulf between high public support and a lack of technical capabilities and political intention to build nuclear weapons.”

South Korea has neither facilities to produce fuel for nuclear bombs nor the technical know-how to design nuclear weapons. And while Mr. Yoon has been more antagonistic toward the North than his recent predecessors and briefly warmed to the idea of going nuclear, there is little political will in the South to pursue atomic weapons.

Strengthening reconnaissance and missile abilities, analysts say, would serve South Korea better and give it the ability to launch pre-emptive strikes against the North.

Building nuclear weapons would be “redundant” and “would not make South Korea any safer,” said Chun Yung-woo, a former national security adviser, “as long as the South Korea-U.S. alliance is alive and well.”

But the future of that alliance is likely to be volatile if Mr. Trump — who tried to negotiate with Mr. Kim face to face — is re-elected in November.

“It’s nice to get along when somebody has a lot of nuclear weapons,” Mr. Trump said of Mr. Kim when he accepted his party’s presidential nomination last month. “I think he misses me, if you want to know the truth.”

For supporters of a domestic nuclear force in South Korea, Mr. Trump’s potential return to power could be a good thing. He once said he would be open to allowing Japan and South Korea to build their own nuclear arsenals rather than depend on the American nuclear umbrella.

“It could open a window of opportunity,” said Mr. Cheong, the pro-nuclear analyst.