China and India, two nuclear-armed powers with a combined population of 2.7 billion, gathered thousands of troops at a disputed border in the Himalayas in 2020 -- the latest confrontation in a long history that includes a war in 1962 and a confrontation near Bhutan in 2017. Weeks of skirmishes led to the first deadly clashes along the un-demarcated border in four decades. A year on, the dispute lingers, talks to resolve the matter remain deadlocked and both sides are shoring up their forces.

1. What’s this dispute about?

In May 2020, China surprised India by deploying troops in three main locations, two of them in Ladakh, a remote part of northernmost India abutting Tibet (an autonomous region of China) and Pakistan-occupied Kashmir. The 3,488 kilometer (2,167 miles) border is ill-defined and the reason for the maneuver was unclear, but earlier actions by India regarding the territories of Ladakh, whose people are culturally close to Tibet, and Kashmir had drawn angry responses from its neighbors. China has accused India of seeking “to undermine its territorial sovereignty.”

2. How bad did it get?

The confrontation was centered on the Galwan River area and Pangong Tso, a glacial lake at 14,000 feet (4,300 meters) in the Tibetan plateau. After weeks of hostilities, 20 Indian soldiers died in June 2020 in a clash with Chinese troops. The PLA Daily reported -- eight months later -- that four Chinese soldiers were also killed in that clash. Tensions flared again 2 1/2 months later after India moved troops to the hilltops on its side of the border at Pangong Tso lake to stop a push by Chinese forces. In September 2020, the two sides renewed pledges to de-escalate tensions after their defense and foreign ministers met for the first time since the standoff began. That was followed by an agreement to stop sending troops to the front line and, in February, confirmation of a pullback from Pangong lake. Multiple rounds of talks since then have yielded little. India says China has broken agreements on maintaining minimum troop presence at the border while China says its military buildup is a “normal defense arrangement.”

3. How old is the India-China border conflict?

It dates back to the 1950s. Skirmishes were reported after India granted the Dalai Lama asylum following an uprising against Chinese rule in Tibet in 1959. War broke out three years later after China objected to India establishing outposts along the effective boundary, established by the British in 1914, between the Tibetan region and Northeast India. The current “Line of Actual Control” that forms the ambiguous border partially adheres to the British-drawn boundaries. Clashes were also reported in 1967 and again in 1987 in what’s sometimes referred to as the loudspeaker war -- no bullets were fired and soldiers simply kept shouting at each other via loudspeakers. Relations improved as the two governments signed five treaties between 1993 and 2013 and -- with economic growth racing ahead in both countries -- China became India’s largest trading partner. The border remained mostly calm through 2017, when troops faced off for several months at Doklam, a plateau near the Indian border that is claimed by both China and Bhutan. The clashes are mostly seasonal, given the harsh winter conditions.

4. What’s different now?

The context, including the coronavirus outbreak. An especially brutal second wave in India in April and May took total infections to more than 30 million people and severely damaged the economy. India’s Prime Minister Narendra Modi has also been shifting his country closer to the U.S. as relations with China have worsened. Since 2017, India has signed crucial communications and arms agreements with the U.S. and blocked dozens of Chinese apps on national security grounds. India has also prevented Chinese companies from taking over local businesses and stepped up road construction in border areas. China has been building border infrastructure for decades, including -- to India’s chagrin -- through disputed areas that link China to Pakistan. Meanwhile, China is getting more assertive. It pressed ahead in the face of international condemnation with a new national security law in Hong Kong, while also getting involved in more military run-ins in the South China Sea and warning Taiwan against any moves toward independence.

5. Will tensions escalate?

Most observers had been speculating that war was unlikely since neither side wanted to escalate matters. One outcome has been closer alignment between India and the U.S. The U.S. has been broadening trade and strategic ties with countries in the Indo-Pacific region. The Quad -- a security framework with the U.S., Japan and Australia -- has been revived and held naval exercises in the Indian Ocean. Still, there’s always a chance border scuffles will resume elsewhere. India has opened a bridge to enable faster movement of troops and artillery in the region of the 2017 border clashes. In the first half of 2021, India added fighter jet squadrons and 50,000 troops, raising its deployment to around 200,000, while Beijing builds bunkers and airstrips, stoking concerns about a possible escalation.

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