The 21st Century will see water become the strategic resource, surpassing even oil as the key concern of meek and mighty alike.
It is no accident, then, that the most war-prone regions of the planet are those areas leading the trend.
Following is a list of countries projected to experience (a) the largest adverse change in population as a percentage of the number of people the local water supply can support, and (b) where that percentage exceeds a threatening threshold (calculated to be 91.2%, half a standard deviation above the global mean as of 2010).
The list speaks for itself; among them are either the most war-prone nation-states on the planet, or states kept from war and collapse only by heavy investment in the means of force.
Table of "Water Danger" countries (worst is first)
Legend: Ongoing War
Peripheral to Ongoing War
Country Proj. pop/capacity %, 2010
Kuwait 104.6%
Gaza Strip 114.3%
Chad 94.0%
Uganda 101.8%
Eritrea 107.4%
Mauritania 94.9%
Comoros 103.5%
Benin 94.9%
Iraq 92.5%
Sudan 93.9%
Burkina Faso 94.2%
Syria 99.8%
Afghanistan 105.5%
Burundi 102.4%
Ethiopia 105.2%
Tanzania 106.9%
Djibouti 108.6%
Togo 104.9%
Pakistan 101.6%
Yemen 130.6%
Philippines 93.7%
El Salvador 99.6%
Tajikistan 106.1%
Oman 131.1%
Kyrgyzstan 97.1%
Interpretation - Hungry people have time to work out an alternative solution to combat over scarce resources.
Water is an acute threat to life; people die in days, not weeks, from its lack. there is a magnitude less negotiating room.
Ergo, the most dangerous places on the planet are those where water resources are strapped.
Now, within a robust trade regime, cities (which have no prayer of supplying their own water) come out nicely, but despite the usefulness of water for transporting goods, water itself is very difficult to transport.
That it is ever transported at all speaks of its critical and near-unique value as a commodity.
As for the above list - it speaks for itself, to the point that everywhere not immediately involved in conflict that is on this list is in grave danger of falling into violence and disarray.
It's that serious.
Oh, and the problem is spreading.
Assuming no deterioration in the water supply of central North America, the United States will be just as war-prone (per this model) as Iraq and Sudan in the early 22nd century.
And that assumes that we will be no more or less avaricious for water resources than the Iraqis or the Sudanese.
If we are more conserving, the danger will be evaded.
If we are more thriftless, the danger point will arrive much sooner.
And I suspect in certain areas of the country, the danger is upon us already.