Despite a cordial Mamallapuram Summit between Prime Minister Modi and the Chinese President, the dispute on the Line of Actual Control has deepened after a gap of several years. What do you think are the reasons behind it?

What Mamallapuram was

• Like Wuhan, it was an informal leaders’ meeting to cool Doklam-era distrust and to talk trade and people-to-people ties.
• It produced atmospherics and working groups, not a settled alignment of the western, middle, and eastern sectors of the LAC.
• Informal summits manage optics; they do not replace the 1993, 1996, and later border agreements that still leave differing perceptions of the line.

Why the dispute deepened in 2020

• Differing LAC perceptions in Ladakh, including the Galwan valley, Depsang, Gogra–Hot Springs, and Pangong Tso, were live military files, not closed political files.
• India’s accelerated border infrastructure, including the Darbuk–Shyok–Daulat Beg Oldi road, reduced the PLA’s earlier time-and-space advantage; China pushed back on the ground.
• China’s wider 2020 assertiveness—Hong Kong, Taiwan, South China Sea, and pandemic diplomacy—made the Western Theatre Command less likely to sit quiet on a grey zone.
• India’s August 2019 changes in Jammu and Kashmir were read in Beijing through Aksai Chin and the CPEC corridor in Pakistan-occupied territory; protest at the UN and later the LAC were the same strategic anxiety in two languages.
• India’s Indo-Pacific tilt, the Quad revival, and closer US logistics sitting beside a still-unsettled border made deterrence and distrust rise together.
• Local patrols, occupancy of heights, and a breakdown of the old ‘no-firearm’ custom turned a map quarrel into casualties in June 2020.

Reasoned balance

• The summit was cordial because both sides wanted a pause, not because the boundary was agreed.
• Deepening after a gap of several years was therefore not a mystery of personal chemistry; it was infrastructure meeting salami tactics on an undefined line, in a harder Chinese and a more aligned Indian year.