In recent years, the disputed border between China and India has become the site of growing tensions. Chinese encroachment has sparked clashes along the mostly rugged, mountainous border, known as the Line of Actual Control (LAC), which threaten to lead to all-out conflict between the two Asian giants.

These mounting tensions affect the United States and its Indo-Pacific strategy. Military hostilities between the two large, nuclear-armed countries risk escalating into a conflagration that could involve a third nuclear power: Pakistan. Such a widening conflict would be catastrophic for the region, though it now remains a remote prospect. More likely, border tensions will continue to simmer as China and India strengthen their military capabilities and build up infrastructure along the border. Washington should assist New Delhi in deterring further Chinese attempts to nibble away at Indian territory and be ready to respond quickly in case events spiral out of control.

If fighting intensifies along the LAC, the United States could support India diplomatically and militarily, but without trumpeting this assistance. Washington could find creative ways to bolster New Delhi’s position even if it will not seek to mediate the conflict. But it must pay serious attention. The United States cannot simply ignore this escalating border dispute until it mushrooms into a full conflict, nor can it stay completely on the sidelines.


Modern China and India have never agreed on the course of their shared border, a boundary inherited from the British colonial era that passes through many remote and largely uninhabited stretches of the Himalayas. The dispute flared into war in 1962, which resulted in a resounding Chinese victory and the loss of territory for India. From the late 1980s until the mid-2010s, the border remained relatively peaceful, and the two sides engaged in sporadic talks to reduce tensions. The two countries hoped to set aside the boundary dispute and focus on other areas of their relationship. But China’s interest in consolidating its hold on Tibet (which is on the Chinese side of the LAC) and its perceptions of India’s strengthening ties with the United States led Beijing to use more strident public rhetoric around 2007.  

Along with its more belligerent statements, China began taking provocative actions along the LAC, leading to two dustups, in 2013 and 2014, and a lengthy standoff in the summer of 2017 in Doklam, where the borders between Bhutan, China, and India converge and where China had tried to build a road. The completion of that road would have given Beijing a commanding military position in the area, allowing China’s People’s Liberation Army to overlook a stretch of India known as the Chicken’s Neck—a corridor connecting India’s northeastern states to the rest of the country. Fortunately, none of these engagements resulted in loss of life.

That changed in June 2020 in the Galwan River valley in Ladakh, in the western sector of the border, where 20 Indian troops and at least four Chinese soldiers were killed in a hand-to-hand brawl. The clash followed a major Chinese military buildup in the spring of 2020 of 30,000 troops with tanks and artillery at five different locations along the LAC, including in areas India regularly patrolled. Beijing also later deployed fighter and bomber aircraft, rocket forces, and air defense radars at several points along the disputed border.

The Chinese and Indian militaries have since pulled back forces from the most contentious positions and established temporary buffer zones, but both sides retain large numbers of soldiers along the tense frontier. A border clash that took place near Tawang, in the eastern Indian state of Arunachal Pradesh, in December 2022 was a reminder that, although recent attention has been focused on Ladakh, many other flash points along the 2,100-mile LAC could erupt into crisis at any moment.

A conflict could erupt along India and China’s 2,100-mile disputed border at any time.

Beijing wants to move ahead with a broader bilateral relationship with New Delhi, regardless of the status of their border dispute, but the latter has not been obliging. It wants to condition the normalization of bilateral ties on China’s willingness to return to the positions along the LAC that existed before May 2020. New Delhi insists that the two sides still need to negotiate the disengagement of their forces in the Depsang Plains, a region in the northern part of the LAC, as well as Charding Nullah farther south. Indian officials believe China wants to force them to accept a “new normal” that would prevent India from patrolling areas over which it has previously held sway, resulting in New Delhi essentially ceding territory it claims.

China’s ample resources enable its armed forces to keep building infrastructure at a brisk pace to support military operations on the border. China is beefing up its military position along the western frontier by constructing and upgrading airports, heliports, roads, railways, and other infrastructure. Beijing’s new roads go through particularly sensitive regions. For example, as part of a large national infrastructure program, China is constructing the G695 highway, connecting Xinjiang and Tibet through the region of Aksai Chin (that India lost to China in the 1962 war), which would allow it to more easily deploy troops to the LAC. Once completed, the highway would become only the second major highway constructed in Aksai Chin since 1955.

Beijing is also building a bridge—its second—across disputed areas of the Pangong Lake in Ladakh, also designed to better facilitate troop deployments to the region. Finally, China has recently erected several large structures along the LAC to house troops during winter. According to one Indian estimate, the expansion of Chinese facilities over the last two years will allow China to garrison 120,000 troops (up from 20,000 troops) within 60 miles of the disputed border facing eastern Ladakh.

Much of India’s troop increases along the LAC since the 2020 clash have come from redeployments and the rebalancing of its forces. For example, in June 2021, India shifted approximately 50,000 troops to the LAC—20,000 of whom were pulled from India’s disputed western border with Pakistan. India has also strengthened its defensive capabilities along the LAC, deploying drones for surveillance operations in eastern Ladakh and conducting airborne drills in the area.

Closer defense ties with the United States have improved the readiness of India’s armed forces and enabled New Delhi to procure more advanced weapons systems. These procurements include systems such as Chinook helicopters for rapid troop transport and potentially armed Predator drones for expanded intelligence, surveillance, and reconnaissance work. India also benefits from an annual military exercise it stages with the United States called Yudh Abhyas (Training for War), which takes place in high-altitude terrain and helps India hone its capabilities against China in high-altitude combat. In early December 2022, the U.S. and Indian militaries completed the 18th edition of these exercises, this time in the mountains of India’s Uttarakhand state, just 60 miles from the LAC. China objected to the exercise, which it said violated the spirit of border agreements made between China and India in 1993 and 1996.


As border tensions between China and India remain high, Pakistan could wind up playing a significant role. The growing closeness of China and Pakistan has alarmed India, which fears that Islamabad would seek to exploit tensions between New Delhi and Beijing. Pakistan has been India’s archnemesis since the creation of both countries in 1947, primarily because of their long-standing dispute over the territory of Jammu and Kashmir. In the event of a war with either China or Pakistan, India now has to grapple with the possibility that the other country would also get involved. Indian strategists increasingly fear that they must prepare the Indian army to fight a war on two fronts. Islamabad would likely exercise caution in any potential border conflict between China and India, but New Delhi must also take into account Pakistan’s strategy and activities in any comprehensive assessment of its border dispute with China.

Following the Galwan valley clash between China and India in June 2020, some senior Indian military officials speculated that Pakistan might try to exploit the fraught moment and attack Indian forces along the Line of Control (LOC) that separates Pakistani-administered Kashmir from Indian-administered Kashmir. Pakistan has thus far stayed out of the fray. In 1962, the last time China and India went to war, pressure from Washington persuaded Islamabad to avoid opening a second front.

Short of opening a second front, Pakistan could still assist China in the event of a future Chinese-Indian border crisis. Pakistan could decide to conduct large-scale military exercises that would suggest readiness and a willingness to enter the fray. Pakistani military and intelligence units could encourage terrorist groups to conduct attacks against targets within Indian-administered Kashmir or in major Indian cities, as they have in the past. Or Islamabad could shift its nuclear posture in a way that would set off alarm bells in New Delhi. These Pakistani moves would force India to consider shifting resources and attention away from the LAC to the LOC, potentially to China’s military advantage.


Indian officials believe China is trying to contain India by forcing it to divert more resources into defending both its western border with Pakistan and its eastern flank with China. Stretched in this way, India is far less likely to challenge China’s efforts to achieve regional hegemony. The violence and military buildup along the LAC in 2020 helped clarify Indian strategic thinking regarding China. Indian leaders now perceive a fundamental challenge from China just as U.S. leaders do.

India, of course, does not seek or expect any direct U.S. involvement in its border dispute with China, but it should be confident that it can count on the United States for support, if requested. In 2020, shortly after the Galwan clash, the United States provided critical information and intelligence, as well as equipment, including leasing two surveillance drones. Senior Indian officials have noted privately that this support during the crisis was significant in helping India defend its borders. The Biden administration’s National Defense Strategy, released in October 2022, also makes clear that the United States would support India in any future border crisis with China.

Still, U.S. officials should take this possible flash point more seriously, mentioning it in every strategic document and speech relating to the Indo-Pacific. The United States could also regularly criticize Beijing’s land-grabbing efforts in multilateral forums, including at the United Nations, the Shangri-La Dialogue, G-20 summits, and the East Asia Summit. Indian media outlets follow mentions of India in Washington closely. By merely referring to U.S. support for defending India’s territorial integrity, White House and State Department officials would earn the trust of India’s government and its public.

India should be confident that it can count on U.S. support.

The United States should also offer India the sophisticated military technology it requires to defend its borders, and initiate the co-production and co-development of such equipment, all while encouraging New Delhi to reduce its dependence on Russian weapons. Although India has increased its total purchases of U.S. weapons by over $20 billion in the last 15 years, it has not made a major military purchase from the United States since a $3.5 billion helicopter deal signed in February 2020. U.S. and Indian national security advisers did discuss the co-production of jet engines in January 2023, an effort that, once agreed, would mark a major milestone in the two nations’ defense partnership.

Washington should also establish or support an organization charged with collating unclassified commercial satellite imagery on the position of Chinese troops along the LAC and disseminate these images routinely for public consumption. This work would help make clear how the Chinese are to blame for upping the ante in their border dispute with India.

Finally, Washington should message Islamabad, encouraging Pakistan to stay neutral in the event of a future flare-up along the Chinese-Indian border. Despite its long partnership with China, Pakistan has recently indicated that it does not wish to become overly dependent on Chinese assistance and would like to improve its relationship with the United States. Pakistan’s former chief of army staff and its current foreign minister both visited Washington late last year. Although the United States will probably refrain from resuming large-scale military aid, it could offer Pakistan’s beleaguered economy badly needed trade and investment, as well as support for an International Monetary Fund package.

If the United States does little to back India in its border dispute with China, the latter would likely be emboldened to continue encroaching on Indian territory. Other allies and partners of the United States would take note of Washington’s seeming indifference to New Delhi’s plight, and the United States would seem an unreliable partner when it comes to countering Chinese aggression. This, in turn, would encourage other Indo-Pacific nations to placate—rather than stand up to—China and its bullying tactics, thus undermining the U.S objective of maintaining a free, open, rules-based regional order that preserves the sovereignty of countries in China’s neighborhood.   

The United States must follow India’s lead when offering military assistance and making statements regarding New Delhi’s border issues with Beijing. Otherwise, India may worry that the United States is needlessly inflaming the problem and recoil from U.S. overtures. Washington needs to carefully craft a low-key but still forward-leaning policy of U.S. support for India. Such a strategy will simultaneously maintain the strong momentum of the strengthening U.S.-Indian partnership while deterring China at the border.

Correction appended, February 17, 2023

An earlier version of this article misidentified a strategy document released by the Biden administration in October 2022. The document in question was the National Defense Strategy, not the National Security Strategy.

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  • LISA CURTIS is Director of the Indo-Pacific Security Program at the Center for a New American Security. She served as Deputy Assistant to the President of the United States and Senior Director for South and Central Asia at the National Security Council from 2017 to 2021.
  • DEREK GROSSMAN is a Senior Defense Analyst at the RAND Corporation and an Adjunct Professor at the University of Southern California. He served as the daily intelligence briefer to the Assistant Secretary of Defense for Asian and Pacific Security Affairs at the Pentagon from 2013 to 2015.
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