Control of transboundary water has become a primary instrument of geopolitical coercion

Dam infrastructure gives upstream nations the ability to reduce, redirect, or weaponise water flows affecting billions of people downstream. Unlike trade sanctions or military threats, water control operates through existing physical infrastructure and is difficult to counter without alternative water sources. China’s position atop the Tibetan Plateau gives it unprecedented leverage over nearly two billion downstream people.

Explanandum

Why has water emerged as a central geopolitical flashpoint in the 21st century, when it was managed through (imperfect) international agreements for most of the 20th?

Substance

The shift has three drivers. First, dam technology has advanced to the point where upstream nations can meaningfully control continental-scale flows — China’s planned diversions total 200.6 billion cubic metres per year. Second, China’s economic ascendance has freed it from the international pressure that might have constrained a weaker state. Third, China’s own water crisis (28,000 of 60,000 rivers lost in 20 years) creates domestic pressure to divert more.

The Tibetan Plateau’s Three Parallel Rivers corridor — where the Mekong, Salween, and Yangtze come within 32 km — creates a chokepoint where small interventions can redirect flows between basins by thousands of miles. China’s damming activities have already been linked to droughts on the Mekong (2019) and floods in Thailand (2024).

International governance has failed because the incentive structure is fundamentally asymmetric: upstream nations have leverage and no reason to concede it. The 2013 Beijing-Delhi MoU was non-binding. The 1995 Mekong Agreement collapsed when China withdrew. India’s 2025 suspension of the Indus Waters Treaty shows even long-standing agreements are fragile.

Water control is also connected to political legitimacy in China — the article draws a line from the Mandate of Heaven through the Grand Canal to the South-to-North Water Transfer Project.

Supports

• India suspended the Indus Waters Treaty in April 2025 — the world’s most durable water-sharing accord
• Ethiopia deployed Russian and Israeli air defence systems around the Grand Ethiopian Renaissance Dam
• China’s Mekong dams linked to downstream droughts (2019) and floods (Thailand, 2024)
• The Daryan Dam diverts 60% of the Sirvan River from Iraq to Iran

Challenges

• Much Chinese dam-building serves genuine domestic needs (flood control, energy, decarbonisation) rather than being purely coercive
• Historical water conflicts have generally been resolved short of war — the “water wars” framing may be overblown
• Downstream nations have their own leverage (trade, diplomatic alliances, military capacity) that the water-focused analysis underweights

Open Questions

• Can desalination genuinely neutralise upstream leverage, or does the infrastructure gap make this decades away?
• Is water control better understood through the lens of natural monopoly (the upstream nation holds an uncontestable position) or through conventional geopolitics?

Source Context

Core argument of the Tabarrok article, developed through discussion of the India-Pakistan, Ethiopia-Egypt, and China-Southeast Asia cases.