In 2017, China watched in awe — and shock — as AlphaGo, an artificial intelligence program backed by Google, defeated a Chinese prodigy at a complex board game, Go. The decisive loss to a foreign computer program, which had similarly trounced a South Korean player, was a sort of Sputnik moment for China.

That year, Chinese officials laid out a bold plan to lead the world in A.I. by 2030, pledging billions to companies and researchers focused on the technology. From this fervor emerged DeepSeek, the largely unknown Chinese start-up that upended the technology landscape by creating a powerful A.I. model with far less money than experts had thought possible.

DeepSeek is private, with no apparent state backing, but its success embodies the ambitions of China’s top leader, Xi Jinping, who has exhorted his country to “occupy the commanding heights” of technology. Mr. Xi wants the Chinese economy to be powered not by old growth engines like debt-fueled real estate and cheap exports, but by the most advanced technologies like A.I., supercomputing and green energy.

For Mr. Xi, this moment helps dent the aura of superiority the United States has held in A.I., a critical field in a fierce superpower rivalry. China has cast itself as a benevolent global partner to developing countries, willing to share its know-how, with Mr. Xi saying that A.I. should not be a “game of rich countries and the wealthy.”

Now, DeepSeek has shown that it might be possible for China to make A.I. cheaper and more accessible for everyone. The question, though, is how the ruling Communist Party manages the rise of a technology that could one day be so disruptive that it could threaten its interests — and its grip on power.

Chinese regulation of A.I. has varied in intensity over the years, depending on where the country assesses its strengths and weaknesses. When the Chinese government was worried it had fallen behind the United States in 2022 after the launch of OpenAI’s ChatGPT, it took a more hands-off approach that ultimately allowed ventures like DeepSeek and others to thrive.

Now that the pendulum has swung the other way, that confidence in the industry could prove to be a “double-edged sword,” said Matt Sheehan, who studies Chinese A.I. as a fellow at the Carnegie Endowment for International Peace.

The party’s “core instincts are toward control,” Mr. Sheehan said. “As they regain confidence in China’s A.I. capabilities, they may have a hard time resisting the urge to take a more hands-on approach to these companies.”

As if to underscore that possibility, DeepSeek’s founder, Liang Wenfeng, was invited to a discussion with Premier Li Qiang on Jan. 20, the same day that the company released its latest and most powerful A.I. model, known as R1.

Mr. Liang’s attendance was all the more remarkable considering DeepSeek had not been considered one of China’s so-called A.I. Tigers. That distinction is reserved for high-profile firms like Zhipu AI, a Beijing-based start-up that has received substantial state investment.

DeepSeek is no stranger to the party’s urge to interfere; that may have inadvertently played a role in its eventual success. DeepSeek had originally trained its A.I. models to make bets on the Chinese stock market. But when regulators targeted such behavior, it pivoted in 2023 to advanced A.I. to conform with China’s industrial policy.

Then it stunned the world by rivaling the performance of its American competitors despite using far fewer of the advanced computer chips that are hard for China to obtain — a technological feat that until recently had not been available. At home, Chinese commentators have held up DeepSeek’s achievement as evidence that U.S. restrictions on exports of A.I. chips to China are ultimately futile (even though the company’s founder has said such limits are a major concern).

Even the recent allegations by OpenAI that DeepSeek improperly harvested its data to build its models have not deterred its fans in China, who accuse the San Francisco company of spreading rumors.

“The U.S. technological sanctions on China have left China with no choice but to develop,” said Sun Chenghao, a foreign relations expert at Tsinghua University in Beijing, echoing a popular sentiment in China. “We can only rely on ourselves.”

A.I. holds a special place in Mr. Xi’s vision of China’s rise, with its potential to help the country overcome many of its biggest challenges like its shrinking work force. China has used facial recognition and algorithms to supercharge its ability to surveil its people and snuff out dissent. The technology is also factoring into China’s military modernization with autonomous weapons systems and even battlefield strategy.

DeepSeek’s development could also advance China’s geopolitical goals. DeepSeek uses an open source model, meaning anyone can peer under its hood and use its technology, unlike leading American companies that use more expensive proprietary software.

“The low cost and open source nature of DeepSeek’s model bolsters the Chinese government’s narrative that China is the place developing countries can look to for A.I. solutions,” Mr. Sheehan said.

How big a player China becomes on the global stage in A.I. could ultimately depend on how the government decides to balance regulations with the freedom that companies and researchers need to do cutting-edge work that allows them to compete with the United States.

Some analysts like Gregory C. Allen, a researcher at the Center for Strategic and International Studies and a former U.S. defense official, said there were most likely no restraints on A.I. development when it comes to China’s military.

“The only thing holding them back is performance,” said Mr. Allen, who in his former job held talks with members of the People’s Liberation Army responsible for assessing the risks of A.I.

The same does not hold true for regulating A.I. in the private sector. The landscape there is dictated by the competing priorities of China’s regulatory agencies, each feeling their way around a technology that many in the world still do not fully understand.

It is clear that the more widely used a technology is, the more the party will want to rein it in. In 2023, just months after ChatGPT set off an investment frenzy over artificial intelligence, China issued rules aimed at controlling what Chinese chatbots say to users, requiring them to reflect “socialist core values” and avoid information that undermines “state power.”

In the case of DeepSeek’s chatbot, this has led to awkward responses to seemingly benign questions like, “Who is Xi Jinping?” Researchers testing its capabilities have found that the bot gives answers that spread Chinese propaganda and even parrot disinformation campaigns.

Some concerns are more existential in nature. A growing chorus of scholars have been sounding the alarm about the potentially catastrophic consequences of losing human control over A.I.

Chief among those voices has been Andrew Yao, a giant in A.I. at Tsinghua University and a recipient of the Turing Award, the equivalent of the Nobel Prize for computing. His influence helped establish what China calls the Global AI Governance Initiative, which was introduced by Mr. Xi in 2023 and included a call to always keep A.I. under human control. Last year, the government also called for the enhancement of A.I. governance “on the basis of human decision-making and supervision.”

Ultimately, A.I. in China may only advance as far as the government decides it can mitigate those risks, said Barath Harithas, an expert on A.I. policy at the Center for Strategic and International Studies, a Washington think tank.

“Overregulation and the need to adhere to ‘core socialist values’ could risk neutering A.I.’s potential,” Mr. Harithas said.

The Federal Aviation Administration was using a backup system to send real-time safety alerts to pilots late Saturday because its primary one was “experiencing a temporary outage,” the Transportation Department said.

“The primary NOTAM system is experiencing a temporary outage, but there is currently no impact to the National Airspace System because a backup system is in place,” Transportation Secretary Sean Duffy said on social media.

Mr. Duffy was referring to “Notice to Air Missions,” the alerts that the F.A.A. uses to share information about hazards in the air or on the ground, such as closed runways, airspace restrictions and navigational signal disruptions.

He said the F.A.A. was working to fully restore the system and that the agency would provide updates on its status every 30 minutes. But he warned of possible “residual” flight delays on Sunday morning.

High above the millions of Hindu pilgrims walking the grounds of the Maha Kumbh Mela, Prime Minister Narendra Modi of India beams down from giant billboards and posters as far as the eye can see. Elsewhere, there are life-size cutouts of the leader, luminous at night, with his hands folded in greeting.

The Maha Kumbh, a spiritual festival widely considered the largest gathering of humanity, is taking place this year in the city of Prayagraj, where the Ganges and Yamuna Rivers meet. Hindus believe that a third, mythical river called the Saraswati joins them there. Throngs of devotees take a dip in the holy waters in the belief that doing so will purge them of sins and grant them salvation.

It is a mesmerizing spectacle. There are ash-smeared monks, naked ascetics, priests with vermilion paste on their foreheads, ordinary pilgrims, tourists with selfie sticks, awe-struck foreigners, entertainers, small vendors and big advertisers. It is also a feat of urban planning, an overnight megalopolis built on land borrowed from the receding Ganges in the state of Uttar Pradesh, with tents, toilets, roads, streetlights and even automated ticket vending machines.

For Mr. Modi and his close ally Yogi Adityanath, the hard-line Hindu monk who is the chief minister of Uttar Pradesh, the Maha Kumbh provides a marketing opportunity like no other. It is a platform to show off India’s achievements — and therefore their own — before a rapt citizenry and a watching world.

The political sensitivity of the event was apparent this past week when 30 pilgrims died and 90 were injured in a stampede, according to official counts. Mr. Adityanath appeared to try to minimize the episode, as it took him nearly 15 hours to acknowledge that people had died and to provide a death toll.

Mr. Modi expressed grief and offered help, but otherwise kept a distance from the tragic news. For him, the Kumbh represents an important opportunity to advertise himself as the man who will transform India into a well-governed, efficient, tech-savvy and business-friendly heavyweight.

A positive picture of the festival also helps Mr. Modi, a Hindu nationalist, to satisfy a desire among his right-wing base to promote a glorious Hindu cultural and religious past.

Mr. Modi “is someone who has mixed religion and politics, religion and state,” said Nilanjan Mukhopadhyay, an author who has followed the rise of the Hindu right as it has sought to uproot the secular foundation laid down by India’s Constitution.

Keenly aware of the importance of image, Mr. Modi has enhanced his power by projecting himself not only as a political leader, but also as the caretaker of Hindu traditions. He is both the prime minister and “the head priest of Hinduism in the entire country” performing rituals familiar to many Hindus in public settings, Mr. Mukhopadhyay said.

Mr. Modi is expected to take his holy dip at the Maha Kumbh on Wednesday, the same day that the capital, New Delhi, holds regional elections. The media spotlight on him that day will spill over to his Bharatiya Janata Party as it contests the election.

Mr. Adityanath has been equally active in seeking political advantage from the spiritual event.

Last month, Mr. Adityanath, who has been seen at times as a potential successor to Mr. Modi, held a special cabinet meeting for state ministers in Prayagraj. There, they announced infrastructure projects and bathed at the confluence of the rivers — yet another sign, Mr. Mukhopadhyay said, of the increasingly blurred lines between religion and state.

A week later, after the stampede, Mr. Adityanath worked to spin the disaster as showcasing the prowess of the Maha Kumbh’s rescue operations.

The Kumbh Mela and other ritual bathing events have been around for centuries. Hindu legend holds that when gods and demons fought over a pitcher, or “kumbh,” of the nectar of immortality, the gods spilled drops in four places — each an Indian city that holds a Kumbh Mela every 12 years.

For decades, the festival was overseen largely by various orders of Hindu monks. But governments have long been facilitators, ensuring that the events are orderly and safe.

Kumbh Mela festivals have steadily increased in size over the decades, from a total attendance of a few million people to hundreds of millions, as better infrastructure and facilities attracted more pilgrims.

The central and state governments earmarked hundreds of millions of dollars for this year’s event, called the Maha Kumbh, or “Great” Kumbh, because it coincides with a rare celestial alignment last seen 144 years ago. The festival began in mid-January and will end late this month.

Government involvement is inevitable given the vastness of the pilgrimage, but “people don’t come to the Mela because it’s advertised or promoted by the government,” said Diana L. Eck, a professor emerita at Harvard Divinity School who worked on a 2015 study called, “Kumbh: Mapping the Ephemeral Mega City.”

Still, Mr. Adityanath has gone to great lengths to pitch this year’s festival as a tourist event, with Kumbh “experience” packages, luxury tents and efforts to attract celebrity guests. As he made it a P.R.-driven affair, some attendees said he had distracted from the essence of the festival.

“Politicians should do politics and saints should do their religious work,” said Narender Kumar Sahoo, a pilgrim from the state of Madhya Pradesh who runs a grocery store in his village.

The stampede also led to criticism from opposition parties that Mr. Adityanath’s courting of wealthy and influential attendees came at the cost of arrangements for ordinary pilgrims.

Amanda Lucia, a professor in the Department for the Study of Religion at the University of California-Riverside, has attended the Kumbh Mela many times. Dr. Lucia recalled being astounded during her first visit to a smaller version of the Kumbh in 1997, boarding a packed train from the Indian city of Varanasi to Prayagraj, where she was forced to sit under a sink for the roughly three-hour journey.

Promotion of the event, both domestically and globally, increased significantly after Mr. Modi came to power in 2014, Dr. Lucia said. In 2019, months before Mr. Modi was elected to a second term, he and Mr. Adityanath upgraded a “half” Kumbh Mela that occurs every six years into a so-called full Kumbh, a move meant to win support for his campaign.

“A lot of people were calling it the ‘government Kumbh’” and complaining that the overtly political ploy had cheapened the event, Dr. Lucia said.

One major change for this year’s Kumbh is its heavy marketing as a cultural and developmental showcase — “The Greatest Show on Earth” for Hinduism — rather than as a religious event. The state has highlighted how revenue from commerce associated with the festival will add to official coffers.

The government of Mr. Adityanath has wowed devotees by showering them with rose petals dropped from helicopters. Billboards and digital displays trumpet the government’s investments in infrastructure. Officials share endless data points, including the number of bathers and foreign tourists, feeding the hype.

State government posters have advertised the Maha Kumbh as “divine, grand, digital” — a modern twist for a country that sees itself as a model of homegrown high-tech innovation.

Digital technology has made it far easier for people to find their way around the temporary city. QR codes provide links to hotels, food, emergency assistance and the Mela administration authorities. Nestled among those offerings is a code with a link to the “achievements” of the state government.

Officials said they were using sophisticated technology powered by artificial intelligence to monitor and manage crowds. At the lost-and-found center, workers have been using facial recognition technology to track missing people.

Private companies have supplied artificial intelligence software that can record specific information like the number of people taking holy dips at a certain hour, said Ashok Gupta, a police inspector overseeing the Integrated Command and Control Center.

The software can also determine the inflow and outflow of people in a certain area and manage the risk of overcrowding by redirecting people, although that system could not stop this week’s stampede.

For many of the millions of pilgrims, however, the marvel of the Maha Kumbh Mela is neither political nor organizational.

Dharmendra Dubey, 28, walked for miles toward the confluence of the rivers, reaching the waters after dark. As he toweled off after his dip, shivering as the temperature hit the low 50s, Mr. Dubey, who works in a private bank, said he felt energized.

Despite the long walk, he said he could go into the cold water again.

“No tiredness now,” Mr. Dubey said. “It’s gone.”