In a cold, isolated Himalayan plateau where three countries converge, an old rivalry is heating up.
New Delhi and Beijing are locked in heated verbal exchanges over a slice of land near the narrow passage that connects India's northeast states with the rest of the country — a strategic link called the Siliguri Corridor but more commonly known as the "Chicken's Neck."
The area in disagreement is where three countries — India, China and Bhutan — converge in a tri-junction, and all three are parties to the simmering dispute.
Tensions flared in mid-June, when China began constructing a road in the disputed Doklam Plateau. Both Beijing and Bhutan claim this territory. The Bhutanese note that the process of the boundary settlement is still under negotiation, and the status quo cannot be changed.
The tiny Himalayan country turned to India, its long-time ally, for help.
"India is de facto responsible for Bhutan's security," explains Sameer Patil, the director of Gateway House, an Indian foreign policy think tank. "China's territorial incursions in the Bhutanese territory threaten Bhutanese — and therefore Indian — security."
The Indian Army has issued no official statement. A spokesman said that "such sensitive issues are best dealt between two nations away from the media glare." He added that the relationship between the two armies is "extremely well managed by a host of mechanisms."
But such mechanisms have evidently not worked in a face-off that has stretched into weeks.
Indian media report that troops were rushed onto the plateau to check China's move, and China is said to have deployed more of its troops to the border region.
Beijing accused New Delhi of a provocation — trampling on an agreed principle "by illegally crossing on to the other country's territory" — and of violating the Convention of Calcutta, an 1890 treaty between Qing Dynasty China and the British Empire, then India's ruler.
China says the agreement grants it access to the region, and claims areas far south of what both India and Bhutan claim.
Before long, videos emerged online of the standoff, showing Indian and Chinese soldiers roughing each other up like schoolboys.
Both sides have been subtly threatening to make this nearly month-long standoff even bloodier. With hardening rhetoric, China told India to heed the "historical lessons" of the 55-year-old war. India's defense minister shot back that "the India of 2017 is different." Beijing retorted: So is China.
In the midst of the standoff, Indian Prime Minister Narendra Modi and Chinese President Xi Jinping warmly greeted each other Friday on the sidelines of the G-20 summit in Hamburg.
Earlier, India's army chief, Gen. Bipin Rawat, had noted, "Even the prime minister has stated for the last 40 years, not even a single bullet has been fired on the Indo-China border."
India undoubtedly would prefer quiet on its east front, as tensions spark with Pakistan over Kashmir further to the west.
Meanwhile, China is sticking to a demand of immediate withdrawal of Indian troops to avoid "any worsening of the situation" on the border. India, however, has indicated it has no intention of pulling back, and that the army is setting up re-supply lines.
The matter has diplomatic hotlines working overtime in hopes of preventing the episode from escalating into something more serious.
But there's no disguising the two countries' deteriorating relations, says Sudha Ramachandran, a Bangalore-based analyst who writes on South Asian politics and security issues. One sore point, she says, is China's refusal to back India's entry into the Nuclear Suppliers Group, countries that control the export of materials that can be used to make nuclear weapons. She also notes Beijing's irritation at India's refusal to join China's ambitious "One Belt, One Road" infrastructure initiative.
And few things inflame passions in Beijing like the Dalai Lama, who has been based in Dharamsala, India, for decades. In April, the Tibetan Buddhist leader visited the far northeastern Indian state of Arunachal Pradesh, territory that China claims. While thousands thronged the Dalai Lama, China denounced him and India for allowing him to go.
Adding to the strains, Beijing seems ever more determined to declare who the next Tibetan spiritual leader will be to succeed the Dalai Lama — who turned 82 Friday.
But the current Chinese build-up "is to diminish India in the eyes of the region," Ramachandran says. It is "to show India's neighbors that they should not depend on India for security as it cannot defend itself against ... a mighty China."
India and China have a complicated history of boundary disputes that dates to the creation of the McMahon Line, a 550-mi. border proposed by the foreign secretary of British India, Henry McMahon, in 1914. It has served as the boundary between India and China, but the Chinese have long disputed its legal status.
It is not possible to verify how many troops either side has massed. Indian media say each side has deployed several thousand.
In this, one of the longest standoffs between the two sides since 1962, China may be worried about a policy frequently uttered but just as frequently denied: that Washington would like to enlist New Delhi in a strategy to "contain" China.
Ashley Tellis of the Carnegie Endowment for International Peace says, "The growing Chinese suspicion that India was casting its lot entirely with the United States has intensified Beijing's determination to be even less accommodative towards New Delhi."
The standoff at Doklam is likely to be repeated "many times over in more places in the months ahead," Tellis warns. "As Chinese road construction inches toward New Delhi's claim lines," he says, "the competition will get even more intense."