Full History of the India-China Border Dispute and the LAC

LAC History

The Line of Actual Control (LAC) is the litmus test of India-China relations, where the maturity, strategy, and diplomacy of both nations are continuously tested.

History of the LAC

India and China—two ancient civilizations that have emerged today as political, economic, and military powers of Asia. The borders between them are not only geographically harsh and inaccessible but also more complex from a diplomatic and historical perspective. The result of this complexity is the “Line of Actual Control” (LAC), which is not merely a disputed boundary line, but a symbol of distrust, military standoffs, and strategic competition between the two nations. This line is not just a demarcation on a map; it is a living document of history, diplomacy, war, and power balance that continues to define the direction of India-China relations.

What is the LAC?

The Line of Actual Control is a sensitive and complex aspect of the India-China border. It is not a legally recognized international boundary but a de facto line that separates the areas under the actual control of the two countries. India considers its length to be approximately 3,488 km, while China claims it to be around 2,000 km. The LAC runs through the Indian states and Union Territories of Jammu & Kashmir (present-day Ladakh), Himachal Pradesh, Uttarakhand, Sikkim, and Arunachal Pradesh. Conditions along the LAC are fluid and ever-changing, making the region a recurring flashpoint for tensions and military conflicts. The absence of a clear demarcation often leads to confusion and standoffs between both militaries.

Historical Perspective of the LAC

Roots in British Era and Boundary Disputes

The foundation of the India-China boundary dispute was laid during British rule when British India initiated several efforts to define its boundaries with Tibet. In 1914, the Simla Convention was signed between British India and Tibetan representatives, wherein the McMahon Line was drawn, separating India’s northeastern region (particularly Arunachal Pradesh) from Tibet. However, China never accepted this agreement, arguing that Tibet was not a sovereign entity but a part of China, and hence had no authority to sign such a treaty. This disagreement remains the root of the current India-China border dispute.

1950: Chinese Control Over Tibet

In 1950, China conducted a military operation and took control of Tibet. This drastically altered India-China relations. India had regarded Tibet as a de facto independent state and maintained historical, religious, and trade relations with it. China’s forceful occupation of Tibet brought greater challenges to India’s border security.

Panchsheel Agreement and India’s Diplomatic Misstep

In 1954, the Panchsheel Agreement was signed between India and China, through which India formally recognized China’s sovereignty over Tibet. This agreement was based on mutual trust and peaceful coexistence. However, under its cover, China steadily strengthened its hold in border regions. India, driven by the “Hindi-Chini Bhai-Bhai” (India-China brotherhood) sentiment, ignored China’s aggressive strategies on the border—an oversight it later paid heavily for.

The 1962 War and the Formation of the LAC

The border dispute between India and China peaked in 1962 when the two countries fought a limited but deadly war. China captured the Aksai Chin region in Ladakh and parts of Arunachal Pradesh. After the war, China declared a unilateral ceasefire and withdrew, but retained control over Aksai Chin. Following this, both armies stationed themselves along their respective zones of control. This de facto military line came to be known as the Line of Actual Control or LAC. It was formally referenced for the first time in the 1993 India-China agreement, but it still remains neither clearly defined nor mutually accepted.

The Problematic Nature of the LAC: Ambiguity and Disputes

The biggest issue with the LAC is that India and China interpret it differently. India believes the LAC is around 3,488 km long, while China claims it to be 2,000 km. It passes through Ladakh (formerly Jammu & Kashmir), Himachal Pradesh, Uttarakhand, Sikkim, and Arunachal Pradesh. This ambiguity causes both militaries to patrol in overlapping claim areas, often resulting in confrontations.

Three Key Sectors of the LAC

India-China border is divided into three sectors:

1. Western Sector

Includes Ladakh, where Aksai Chin is the most disputed region. China seized Aksai Chin during the 1962 war and continues to control it, although India considers it an integral part of Ladakh.

2. Middle Sector

Includes Uttarakhand and Himachal Pradesh. This region is relatively peaceful with limited disputes. Both nations have exchanged maps here, bringing some clarity.

3. Eastern Sector

Includes Arunachal Pradesh, over which China is the most aggressive. China refers to it as “Southern Tibet” and claims the entire state. The 2017 Doklam standoff also occurred near this sector, although it happened in the tri-junction area of Sikkim-Bhutan-Tibet and not within Arunachal.

The diverse nature and geopolitical relevance of these three sectors make the India-China border dispute extremely complex.

Recent Tensions – From Galwan to Tawang

In recent years, border tensions and confrontations have surged. The Galwan Valley clash of June 15, 2020, was particularly significant. In this violent clash, 20 Indian soldiers were martyred. China acknowledged only 4 casualties, although some reports suggest their death toll was 38 to 45 soldiers. This was the deadliest confrontation since 1967.

In addition, tensions flared at Pangong Tso Lake and the Finger Area. India claimed territory up to Finger 8 but controlled up to Finger 4, while China claimed till Finger 4 and controlled from Finger 5 to 8. In 2020, China moved its troops up to Finger 4, escalating the situation.

China also made intrusion attempts in the Tawang sector of Arunachal Pradesh in 2022 and 2023, which were thwarted by Indian forces. A clash in 2022, though less fatal than Galwan, showed that the tension persists.

Strategic and Diplomatic Dimensions

India has significantly strengthened its military and diplomatic strategies along the LAC to counter China’s increasing pressure. In recent years, India has rapidly developed its border infrastructure, including airstrips, roads, bridges, bunkers, and troop deployment. Now, India is no longer lagging in border development and is focusing on accessibility through tunnels, roads, and logistics bases.

During Operation Snow Leopard in 2020, Indian forces gained control of strategic heights around Pangong Tso Lake and other areas in eastern Ladakh, providing India with a military and diplomatic advantage. This compelled China to withdraw from several contested points.

India and China have conducted multiple rounds of military and diplomatic negotiations to resolve the dispute. Special representatives have been appointed by both sides, and high-level talks continue. However, China’s duplicity and frequent violations of agreements continue to obstruct a permanent solution. Despite agreements on patrolling and troop withdrawals in some areas, ground-level tension and distrust remain.

The Future of the LAC

The LAC holds immense significance for both nations, but their perspectives differ widely. For India, the LAC is more than just a line—it represents national integrity and sovereignty. It is the physical line where Indian and Chinese forces face each other, and India considers it an essential part of its territorial unity, despite it not being an internationally recognized boundary.

For China, the LAC is part of its expansionist policy. It has never fully accepted the LAC, keeping the dispute alive. The lack of transparency and trust on the border continues to fuel conflict.

India has adopted a more assertive and strategically robust defense policy. Instead of merely reacting, it is now actively strengthening its border presence through the development of roads, airbases, and bunkers. Initiatives like ‘Make in India’ and indigenous defense production have bolstered India’s military self-reliance. Additionally, India has strengthened its global diplomatic presence through alliances like QUAD, placing strategic pressure on China.