In May, after Canadian police arrested and charged three Indian citizens based in Edmonton for last year’s murder, India’s foreign minister suggested that the killing was related to gang violence and chided Canadian authorities for having allowed “organized crime from India, specifically from Punjab, to operate in Canada.”

It isn’t uncommon to detect a degree of belligerence in how Indian officials talk about these matters. When I visited Delhi last fall, the mood in the capital over Canada’s allegations was one of defiance. Pankaj Saran, who served as India’s deputy national-security adviser from 2018 to 2021 and now runs NatStrat, which researches security issues, contrasts India’s self-assuredness on the international stage today with its diffident foreign policy of the 1980s. “Back then, we were literally riding the coattails of the Soviet Union,” he told me. But as the world’s fifth-largest economy, India no longer has any reason to be timid. “Today,” he says, “we have a government that believes we’ve been taking the hit for far too long.”

The Indo-China war of 1962 was precipitated by a series of border clashes not too different from those of recent years. The earlier ones were about more than territorial disagreements, though. China was smarting from India’s embrace of the Dalai Lama, who had fled Tibet in 1959 and established a government in exile in Dharamshala, India. At this point, the two countries were still young in their modern incarnations; neither had an impressive military. But the People’s Liberation Army of China was stronger, and Indian troops suffered a humiliating defeat, which impelled India to increase military spending. A month after the war began, around the same time that India requested that the United States intervene with air support, China declared a unilateral cease-fire, effectively ending the conflict. India had to accept that Aksai Chin, an area of 15,000 square miles that it claimed as its own, would remain under Chinese control.

An uneasy truce held for the next several decades, except for a confrontation in 1986-87 on the eastern stretch of the border, in a valley bordering the hilly and verdant Indian state of Arunachal Pradesh. Indian officials say that the status quo began to change in 2013, right after Xi Jinping became China’s president. In April of that year, weeks before the newly anointed Chinese premier Li Keqiang was scheduled to visit Delhi, Chinese troops entered the Depsang Plains in Aksai Chin and set up an encampment just 20 miles south of an Indian military base. Alarmed by the incursion, the Indo-Tibetan Border Police pitched its own tents about 300 yards away. The standoff continued for about three weeks before it was resolved through talks, and both sides removed their encampments.

Less than a year and a half later, days before Xi’s state visit to India in 2014, Chinese troops entered Chumar, in eastern Ladakh. “This time it was deeper into our territory and on a broader swath,” Ranade told me when we met for coffee in Delhi last summer. Modi reportedly raised the matter with Xi during a dinner in Ahmedabad, and weeks later the troops withdrew from the area.

Some Indian officials back then were of the view that Depsang and Chumar were one-off incidents, attributable solely to People’s Liberation Army commanders on the ground locally, but Ranade was certain that Beijing had to be involved. In those days, he prepared a regular report on China for a think tank, based on his analysis of Chinese materials. He learned a few things that were troubling: The P.L.A. was conducting more exercises in Tibet (and using more weapons in them) than ever. “Then they began having paratrooper exercises there, and they had some kind of aircraft coming in there, which was again unusual,” Ranade told me. The increased military preparedness signaled an aggressive posture. “I said: ‘Look, there’s something brewing. I can’t tell you what it is, but it doesn’t look good to me.’”

The next notable confrontation unfolded in Doklam, a plateau roughly 800 miles to Ladakh’s east, close to where the borders of Bhutan, China and India meet. China claims Doklam as its territory, while India and Bhutan maintain that the area is a part of Bhutan. Bhutan has historically relied on India’s help to defend its borders, so when China started to build a road into Doklam in June 2017, Indian troops entered the area to stop that construction, and the two sides formed human walls that faced off against each other.

Srikant Kondapalli, a professor of China studies at Jawaharlal Nehru University, recounted to me what he had learned from an Indian brigadier about how Indian forces attempted to gain a psychological advantage in the conflict. “They put together some 40 to 50 especially tall Indian soldiers, all above six-and-a-half feet, and pitched them against the Chinese, who were a lot shorter,” Kondapalli says. He believes the intimidation tactic helped India as the troops went eyeball to eyeball. Scuffles broke out intermittently. The face-off lasted 73 days. India was able to shut down the road project, which would have put the Chinese military within striking range of the Siliguri corridor — a strategically vital sliver of land that connects India’s northeastern states to the rest of the country.

‘If this was not premeditated, how come the Chinese had iron clubs with spikes and barbed wire?’

Then came the clash in the Galwan Valley, during a June night in 2020. The valley is along the Galwan River, just southwest of Aksai Chin. Tensions had been simmering there since April, when Chinese troops pitched tents in the valley. The Indian military saw this as yet another incursion across the Line of Actual Control by the P.L.A. According to Indian officials, China agreed to withdraw from these areas, including from the valley.

The violence in mid-June began when Col. Bikkumalla Santosh Babu, who commanded an Indian Army unit tasked with monitoring the Chinese withdrawal from Galwan, reportedly got into a heated exchange with Chinese soldiers who were supposed to have left by then. Although the Indian Army hasn’t released details, I gathered the broad outlines of the incident from Indian security and intelligence sources, including Jayadeva Ranade, whose own understanding of the incident comes from a careful reading of media reports. He told me that Babu, who was accompanied by two men when he walked over to the Chinese camp, was attacked. “One of the men came back and told the others in his unit,” Ranade said, “and they went over and there was a showdown.”

The Chinese soldiers were apparently armed with metal clubs studded with spikes and wrapped in barbed wire. The fighting, which continued late into the night and involved dozens of men on each side, might have been less bloody if the soldiers had used their firearms. In all, 20 Indian soldiers, including Babu, were killed. State media in China later reported four deaths on the Chinese side, although Indian officials claim the number was significantly higher.

The brutal fighting in Galwan didn’t strike Ranade as entirely unexpected. He saw it not as a fracas that spiraled out of control but rather an attack planned by the Chinese — the kind of thing he had been warning his colleagues about. As he put it to me, “If this was not premeditated, how come the Chinese had iron clubs with spikes and barbed wire?” Ranade said he had come across calls put out by P.L.A. units inviting bids to supply similar weapons as recently as March 2023, which indicated continued hostile intent. “So obviously, they are preparing.”

In 2017, Xi Jinping wrote a letter to two sisters from a yak-herding family in Lhunze County, in southern Tibet, adjacent to Arunachal Pradesh, thanking them for their efforts in safeguarding the border. According to Chinese state media, the two Tibetan women and their father had been the sole inhabitants of their town Yumai for a period of years until the mid-1990s; its population has since risen to more than 200. In his letter, which was widely publicized in China, Xi expressed hope that the family would inspire other herders to put down roots in the area like “galsang flowers” and become guardians of Chinese territory.

Since taking over as president, Xi has repeatedly talked about being uncompromising in protecting the country’s “core interests” — a term that is understood to include China’s territorial and sovereignty claims. Under Xi, the country has converted coral reefs and sand piles dredged up from the seabed in the South China Sea, which it maintains belongs almost entirely to China, into artificial islands that are now heavily militarized with missiles and air strips. Xi has also emphasized China’s commitment to realizing its long-held dream of “reunification” with Taiwan, which split from mainland China in 1949. A similar priority is the consolidation of Chinese control over Tibet by squashing a decades-long Tibetan independence movement. China’s aggressive stance along the border with India, Kondapalli told me, is being driven by the same overarching goal of asserting sovereignty over disputed areas.

A senior Indian intelligence official I met with in Delhi last year explained that China’s hostility along the Line of Actual Control had two strategic objectives: diminishing India’s impact in its own backyard and tying down India’s military in order to weaken India’s broader geopolitical influence. “We are the big brother in our region: Bangladesh, Nepal, Sri Lanka — everyone looks to India when they have a problem,” he said. “China wants to dent us by saying, ‘How is India going to be your net security provider when they can’t handle their own risk?’” He attributed Chinese cyberattacks directed at India to the same motive: a desire to reduce India’s standing. China’s hostility, he said, was aimed at diluting India’s participation in strategic alliances that have emerged to counter Chinese threats.

One such example is the Quadrilateral Security Dialogue, or Quad, a group made up of India, the United States, Australia and Japan, which share the goal of preventing China from dominating the Indo-Pacific. The Chinese, according to the intelligence official, “don’t want India to be the long arm of the United States in this region or to be an active part of things like the Quad, which brings you back to the border issue. They want to keep us pinned down on the land borders because the future of geopolitics is maritime. They don’t want us to lift our heads.”

China’s economic muscle has helped expand its influence in the region in ways that India hasn’t been able to match, the official told me. As part of its Belt and Road Initiative, which Xi began in 2013, China has invested in infrastructure projects in every one of India’s neighbors. “We call them strategic projects because they are going into them with no consideration of what they’ll get back in business terms,” he said. What China was gaining from these investments was “massive leverage.” Not only was India unable to compete in terms of resources, he added, India was also not allowed to operate as he claimed the Chinese do. “They literally come with bags of cash,” he said. “We have to have parliamentary approval, this approval, that approval.”

At the Tibetan border, this approach has taken a more physical form, as China has built more than 620 new “xiaokang” — or “moderately well-off” — villages all along the Tibetan border. Billions of yuan have been spent on roads, power stations, schools and health care facilities to support these villages. Each settlement consists of about 100 homes equipped with modern amenities like heating and internet connectivity. A mix of Tibetans and Han Chinese — many of whom are ex-military men — have moved into the villages, Kondapalli says, effectively changing the demographics of the area and enhancing Beijing’s ability to crush Tibetan resistance.

“These settlements are de facto intelligence outposts,” Kondapalli says. In contrast to the xiaokang villages, which are right next to the Line of Actual Control, the settlements on India’s side are 20 to 30 miles inside Indian territory. That gives the settlers in these villages an opening to encroach upon land that belongs to India, Kondapalli says.

Indian authorities see the establishment of these border villages as buttressing a strategy of gradual encroachment — or “salami slicing,” as it’s known among security strategists — that China has practiced over the years in the South China Sea and is now attempting to replicate along the Line of Actual Control. The high-ranking Indian intelligence official I spoke with in Delhi explained to me how the Chinese military had been operating on the border. “It’s very simple, but very clear,” he told me over breakfast on the patio of a Delhi hotel. “It starts with their yaks coming into pastures that are common grazing grounds at the border. After a few weeks of the yaks hanging around, the herdsman will come. Then, they start making trails for the herders. And then, because there are herders and yaks there, the P.L.A. will come, saying, ‘These are our nationals — we’re just checking on them.’”

The official went on: “Once the troops start coming in for patrols, then they’ll pitch tents, saying, ‘Our troops need to rest.’ The next thing they’ll do is, ‘The trails are not good enough, let’s start making roads.’ Then they’ll prevent our patrols from coming into that area. Once the roads are properly made, the tents will become cemented structures. So, in about eight to nine steps, they will create new facts on the ground and say, ‘This is ours.’” Effectively, winning a war without firing a shot.

That’s what the P.L.A. appears to have been aiming for, not just in the Galwan Valley but also in several areas along the border in eastern Ladakh that Chinese troops moved into in the spring of 2020. The clash at Galwan was followed by a withdrawal from that site by both sides, but Chinese soldiers continued to occupy other areas, including those on the banks of Pangong Lake, whose westernmost edge lies 50 miles to the south of the Galwan Valley.

India fought back. On the evening of Aug. 29, 2020, troops from a secretive Indian guerrilla force, together with soldiers from the Indian Army, began ascending the slopes of a mountain in eastern Ladakh. The mountains are part of the Kailash Range, a chain of rugged peaks, the tallest of which reach 22,000 feet, beginning near Pangong’s southern bank and extending southeast for some 500 miles. Because of the difficult terrain, the heights along the range were left unoccupied by both India and China after the 1962 war. But now, nearly six decades later, Indian Army commanders hoped to take control of several of these hilltops.

As Lt. Gen. Y.K. Joshi, the top commander in charge of the operation, later disclosed in media interviews, the operation, called Snow Leopard, had been planned as a response to the P.L.A.’s incursions. By the night of Aug. 29, Indian troops were in possession of a strategic peak. The following morning, Indian tanks rolled up a mountainside several miles southeast on the range, enabling the Indian Army to occupy a high mountain pass known as Rezang La, a strategic location overlooking a Chinese garrison stationed at Moldo on the other side of the range. By the time the P.L.A. could bring its equipment and troops up the slopes on their side, Indian troops already had the advantage.

The action was “well planned, well thought out and executed, achieving total surprise,” Joshi said in a video interview with Nitin Gokhale, a veteran Indian military journalist who runs a foreign-affairs website called Stratnews Global. (The Indian Army has not officially released any information about the operation, but I got a summary description of it from Gokhale.) The Indians suffered one casualty: 53-year-old Nyima Tenzing of the guerrilla Special Frontier Force, which was established 60 years ago to conduct covert operations against China. Tenzing, like other troops who make up the S.F.F., was of Tibetan origin and died from a land mine left behind after the 1962 war.

As Joshi explained to Stratnews, India’s goal in taking the Kailash heights was to compel China to withdraw from the areas occupied by the P.L.A. after their incursions earlier that month. The strategy gave India leverage in negotiating with China, and ultimately led to success: In February 2021, the P.L.A. dismantled its structures and pulled its soldiers back from those sites in exchange for Indian troops vacating the hilltops.

That doesn’t mean, however, that the Chinese have given up. In fact, the P.L.A.’s military presence in the broader area north of Pangong Lake has increased significantly since 2021. According to an analysis by the Center for Strategic and International Studies of satellite images taken on Oct. 4, 2022, the Chinese have built a new P.L.A. divisional headquarters just north of Pangong, just three and a half miles from the Line of Actual Control. Its support buildings are, the C.S.I.S. reports, “flanked by a bevy of trenches and revetments for storing and securing equipment.”

At the end of last August, China’s Ministry of Natural Resources released a new map that rendered Aksai Chin and Arunachal Pradesh as Chinese territory. China has published such maps before. But the timing of the new release — less than two weeks before India was to host the G20 summit in Delhi — suggested that it was a calculated jab intended to undermine India precisely when the country hoped to showcase its rising influence. A government spokesman said such actions by China served only to “complicate the resolution of the boundary question.”

India sees China employing similar tactics to try to pressure India on Arunachal Pradesh, which the Chinese government calls Zangnan. In April, China’s Ministry of Civil Affairs announced that it was renaming 30 places in the region — the fourth such move since 2017. In March of last year, China chose not to send its delegate to a G20 event hosted by India in Itanagar, the capital of Arunachal Pradesh, as a reminder that it considers India’s rule there illegitimate. “When there’s a delegation of Indian bureaucrats traveling to China, the Chinese embassy here in Delhi will not issue a stamped visa to the delegate who belongs to Arunachal Pradesh,” says the former diplomat now at the nonprofit Buddhist organization. Instead, embassy officials permit entry by stapling an unstamped piece of paper to the passport. “They say the individual is welcome because his land is a part of China.” The result, the former diplomat told me, is that the Indian government then can’t send that delegate because doing so would register approval of China’s position.

India has its own anxieties about Indians living near the border: It worries that they might shift their allegiance to China.

One reason for China’s interest in Arunachal Pradesh, especially its district of Tawang, is the existence of Buddhist holy sites in the state, including the Tawang monastery. Founded in the late 17th century, it is the world’s second largest Buddhist monastery, after the Drepung monastery in Lhasa, Tibet. The Tawang monastery was the Dalai Lama’s first refuge in India when he fled Tibet in 1959, crossing over into Arunachal Pradesh after an arduous trek through the mountains. Derek Grossman, of the RAND Corporation, explains that China wants Tawang because it believes that control over what is currently the most important center of Tibetan Buddhism outside Tibet will help consolidate its hold over the Tibetan population. “They have some fears that because India continues to give safe refuge to the Dalai Lama, at some point the Dalai Lama could return to Tawang and use it as leverage to galvanize the Tibetan people to try and declare independence from China,” Grossman says.

India’s government has its own anxieties about Indians living close to the border: It worries that they might shift their allegiance to China. Arunachal Pradesh, like much of India’s northeast, is less developed than other parts of the country; many rural communities in remote areas live in relative isolation. Yeshi Phuntsok, a retired government employee who lives in Tawang, told me that even 20 years ago, many people in the village where he grew up were not fully aware that they were Indians. “They didn’t know there was a country called India or that there was a country called China,” he says. Over the years, outreach efforts by Indian authorities have helped change that, he says: “Now, they understand that India is their country.”

This fledgling, still-forming sense of Indian identity in parts of the border population is another reason the xiaokang villages built by China are a source of concern for the Indian government. “Their thinking is that when they publicize the development of their villages, people on our side of the border will look at that and say, ‘Oh, we are so badly off,’” the Indian intelligence official I had breakfast with told me. “And the Tibetans will see that Arunachal is so poor by comparison.”

Better cellular connectivity in China’s border villages is a source of envy across the Line of Actual Control, where citizens in some areas are able to receive signals from Chinese cellphone towers. Phones can automatically switch to the Chinese network near the border, Phuntsok told me. Earlier on the day we spoke, he had visited an area close to the Line of Actual Control. “Right after I got there, I noticed that my phone was showing 3:30 p.m.,” he said. For a little while, Phuntsok puzzled over how the time could have passed so quickly. He then realized the phone was showing Chinese time, which is two hours and 30 minutes ahead of Indian time there.

Ngawang Tashi, a Buddhist monk from Arunachal Pradesh, told me that China’s attempts to woo India’s predominantly Buddhist border population is part of a larger effort to “sinify” Buddhism — that is, dilute its Tibetan identity and make it more Chinese. He said he had heard about the Chinese government offering houses and financial benefits to Indian yak herders to get them to settle in some of the newly built villages.

“Most people here are loyal to India and followers of His Holiness the Dalai Lama,” he told me. But after the current Dalai Lama is gone, that could change, he added. “They can be swayed when there is money being offered.”

Belatedly, the Indian government has responded to China’s xiaokang villages with a “vibrant villages” program, announced in April last year. Over the next decade, the government says, it plans to invest $600 million in the development of about 3,000 villages that are already settled along the Line of Actual Control, from Ladakh to Arunachal Pradesh. By building roads, dams, schools and hospitals, and by improving telecom services throughout this stretch, authorities hope to give people in border communities a reason to stay where they are and stay loyal to India.

The skirmishes of the past few years have had a silver lining, says Claude Arpi, a longtime scholar of Tibet and Indo-China relations who is currently a distinguished fellow at the Center of Excellence for Himalayan Studies at Shiv Nadar University. It has forced the two sides to come to formal agreements about the border at certain places in Ladakh. “In fact, this is the first time that a map for the L.A.C. exists for this area,” Arpi told me.

Disagreements about the boundary persist elsewhere, however, including Demchok and Depsang. It’s unclear if those will be resolved anytime soon, even though Modi and Xi Jinping agreed at a summit in South Africa last August to expedite “disengagement and de-escalation” on the border, according to an Indian government spokesman. Despite his party’s loss of its majority in the recent election, Modi’s decision-making power on nationalistic issues like border disputes with China is unlikely to diminish in his third term, which in turn means India’s assertiveness along the Line of Actual Control is likely to continue. “Today, after what happened in Galwan, there is no question that China can come more than a few hundred meters inside India’s territory,” Arpi says. “India has responded very strongly for once.”