The Next World War Won't Be Over Oil — It Will Be Over Water
We have spent the better part of a century waging wars, toppling governments, and rewriting alliances over petroleum. The logic was simple: control the oil, control the economy, control the world. But while diplomats and generals were busy mapping pipeline routes and negotiating OPEC quotas, a far more elemental crisis was building beneath their feet.
Water — the molecule that constitutes sixty percent of the human body, irrigates the crops that feed eight billion people, and cools the data centers powering the AI revolution — is running out. Not in some abstract, distant-future sense. Right now. The aquifers are collapsing. The rivers are shrinking. And the treaties that once held thirsty nations in tenuous equilibrium are fraying at every seam.
By 2030, the United Nations projects that 2 billion people will live in regions of absolute water scarcity. That is not a projection of discomfort. It is a projection of conflict.
The Nile: A Dam and a Civilizational Threat
Nowhere is the collision between water need and geopolitical power more visible than along the Nile. For millennia, Egypt's identity — its agriculture, its mythology, its very survival — has been synonymous with the river. Today, 97% of Egypt's freshwater comes from the Nile. There is no Plan B.
Then came the Grand Ethiopian Renaissance Dam.
Ethiopia began construction on GERD in 2011, a massive hydroelectric project on the Blue Nile designed to lift tens of millions out of energy poverty. The engineering is impressive: 6,450 megawatts of capacity, a reservoir that can hold 74 billion cubic meters of water. For Addis Ababa, GERD is a sovereignty project, proof that Africa's second-most-populous nation will no longer subordinate its development to colonial-era water agreements it never signed.
For Cairo, it is an existential threat.
Egypt has warned — repeatedly, and with increasing directness — that any significant reduction in Nile flow could devastate its agricultural sector, displace millions of farmers in the Delta, and trigger the kind of internal instability that no government can survive. Former President Sisi stated publicly that "all options are on the table," language that in diplomatic parlance sits one step below a declaration of war.
A decade of negotiations mediated by the African Union, the United States, and the World Bank has produced no binding agreement. Ethiopia has proceeded with filling the reservoir. Egypt has expanded its military cooperation with Sudan and Eritrea. Both sides are now engaged in what analysts call a "hydro-strategic encirclement" — building alliances and infrastructure not to fight a war, but to be positioned to win one if it comes.
The Nile crisis is not hypothetical. It is happening.
India-Pakistan: The Indus Under Pressure
South Asia presents a different geometry of the same problem. The Indus Waters Treaty of 1960, brokered by the World Bank, has been called one of the most successful water-sharing agreements in history. It survived three wars, nuclear tests, and the Kargil crisis. For decades, it was proof that rational self-interest could override even the deepest enmity.
That treaty is now in serious jeopardy.
India controls the headwaters of all six rivers covered by the agreement. As Himalayan glaciers retreat — some studies project a loss of one-third of their volume by 2100 — the total flow available for division is shrinking. India has accelerated hydroelectric dam construction on its allocated rivers, projects that Pakistan alleges violate the treaty's technical provisions on water storage and diversion timing.
In 2023, India issued formal notice to renegotiate elements of the treaty, a move Islamabad described as "tantamount to an act of aggression." Pakistan's agricultural heartland, the Punjab, depends almost entirely on the Indus system. A 20% reduction in flow would devastate wheat and rice production in a country where 40% of the labor force works in agriculture.
The stakes are compounded by population. Pakistan is projected to reach 400 million people by 2050. India will have surpassed 1.6 billion. Both nations are nuclear-armed. Neither can afford to lose access to the rivers that feed their people.
Climate change did not create this tension, but it is compressing the timeline in which it must be resolved. The glaciers will not wait for diplomats.
The Colorado River: Collapse in a Superpower
If the developing world's water crises seem remote, consider what is happening inside the United States. The Colorado River — which supplies water to 40 million people across seven states, irrigates $15 billion in annual crop production, and fills the reservoirs behind Hoover and Glen Canyon dams — is in structural deficit.
Lake Mead, the largest reservoir in the country, has fallen to levels not seen since the 1930s when it was first being filled. Lake Powell is not far behind. The Bureau of Reclamation has imposed unprecedented mandatory cuts on Arizona, Nevada, and Mexico, and California is facing pressure to accept reductions it has historically resisted.
The Colorado River Compact of 1922 allocated water based on flow estimates from one of the wettest periods in the past five centuries. The actual long-term average flow is at least 15% lower than what the compact assumed. Twenty-first century megadrought, driven by rising temperatures, has reduced flows even further. The river is now over-allocated by roughly 3 million acre-feet per year.
In practical terms, the American Southwest is consuming a river that no longer exists in the quantities promised. Cities like Phoenix, Las Vegas, and Los Angeles have invested heavily in conservation, recycling, and alternative supplies, but the math does not close. Agriculture accounts for roughly 70% of Colorado River consumption, and the political power of farming interests in states like California and Arizona makes the reallocation conversation extraordinarily difficult.
The Colorado is not going to spark an armed conflict between US states. But it is producing the kind of zero-sum interstate litigation, federal intervention, and community-level desperation that reshapes political coalitions and erodes institutional trust. It is a preview of what water scarcity does to governance even in wealthy, stable democracies.
Desalination: The False Promise
Whenever water scarcity enters public discourse, desalination is offered as the technological savior. Just convert seawater to freshwater — problem solved.
The reality is far less convenient.
Desalination works. Israel has demonstrated this at scale, meeting roughly 80% of its domestic water needs through a network of reverse osmosis plants along the Mediterranean. Saudi Arabia, the UAE, and Singapore have made similar investments. The technology is proven.
But it is expensive. The Sorek B plant in Israel, one of the most efficient in the world, produces water at approximately $0.50 per cubic meter. That sounds cheap until you consider that large-scale agriculture requires water at a fraction of that cost. No nation can affordably desalinate its way to food security.
Desalination is also energy-intensive. Reverse osmosis requires roughly 3-4 kilowatt-hours per cubic meter of output. For a country trying to desalinate at the scale of, say, Egypt's agricultural needs, the energy requirement would exceed the country's current total electricity generation capacity.
And then there is brine. For every liter of freshwater produced, desalination generates roughly 1.5 liters of hypersaline waste. This brine, when discharged into coastal waters, devastates marine ecosystems. The Arabian Gulf, already one of the saltiest bodies of water on Earth, is measurably becoming more saline as desalination plants along its shores dump millions of cubic meters of brine daily.
Desalination is a tool. It is not a solution. And framing it as one obscures the political choices that must be made about who gets water, how much, and at what cost.
Two Billion Under Stress
The UN's 2030 projection — 2 billion people in absolute water scarcity — is not distributed evenly. It concentrates in precisely the regions least equipped to manage it: the Sahel, the Horn of Africa, South Asia, the Middle East, and parts of Central Asia.
These are regions already marked by fragile governance, rapid population growth, high dependence on agriculture, and a history of inter-ethnic or cross-border conflict. Water scarcity does not create wars from nothing. It accelerates existing fault lines. It turns a manageable dispute into an unmanageable one. It transforms migration from a trickle into a flood.
Syria offers the template. The drought that struck the Fertile Crescent between 2006 and 2010 was the worst in the region's recorded history. It drove 1.5 million farmers off their land and into cities already strained by Iraqi refugees and government neglect. Researchers at Columbia University and elsewhere have drawn a direct, if not singular, causal line between the drought, the internal displacement, and the social unrest that preceded the 2011 uprising.
No one claims that drought caused the Syrian civil war. But the war would have been far less likely without it.
Now multiply that dynamic across two dozen countries simultaneously.
What Comes Next
The policy responses available are well understood. Drip irrigation. Wastewater recycling. Aquifer recharge. Demand-side pricing that reflects water's true scarcity. International frameworks that bind upstream and downstream nations to enforceable sharing agreements. Investment in climate-resilient crop varieties.
None of these are technologically exotic. All of them are politically difficult.
The uncomfortable truth is that water scarcity is, at its core, a governance failure. There is enough freshwater on this planet to sustain its population — but not if it is allocated by colonial-era treaties, priced at zero, wasted in flood irrigation, or hoarded by nations with the geographic luck to sit upstream.
The wars of the 21st century may indeed be fought over water. But they will not be fought because there is too little water on Earth. They will be fought because we could not summon the political will to share it.
The Nile is filling a dam. The Indus is losing its glaciers. The Colorado is drying up. And 2 billion people are watching the faucet, waiting to see if anything comes out.
The clock is running. The question is whether our institutions can move faster than the water table is falling.
Dalia Khoury is a hydropolitics researcher and policy analyst specializing in transboundary water governance, climate-driven resource conflict, and Middle Eastern security dynamics.