This not-so-positive prediction will focus on United States and Mexican geopolitics as it relates to climate change between the years 2040 to 2050. As you read on, you’ll see a United States that becomes increasingly conservative, inward-looking, and disengaged with the world. You’ll see a Mexico that has exited the North American Free Trade Area and is struggling to avoid falling into a failed state. And in the end, you’ll see two countries whose struggles lead to a rather unique civil war.

But before we begin, let’s be clear on a few things. This snapshot—this geopolitical future of the United States and Mexico—wasn’t pulled out of thin air. Everything you’re about to read is based on the work of publicly available government forecasts from both the United States and the United Kingdom, a series of private and government-affiliated think tanks, as well as the work of journalists like Gwynne Dyer, a leading writer in this field. Links to most of the sources used are listed at the end.

On top of that, this snapshot is also based on the following assumptions:

Worldwide government investments to sizably limit or reverse climate change will remain moderate to non-existent. No attempt at planetary geoengineering is undertaken. The sun’s solar activity does not fall below its current state, thereby reducing global temperatures. No significant breakthroughs are invented in fusion energy, and no large-scale investments are made globally into national desalination and vertical farming infrastructure. By 2040, climate change will have progressed to a stage where greenhouse gas (GHG) concentrations in the atmosphere exceed 450 parts per million. You read our intro to climate change and the not-so-nice effects it‘ll have on our drinking water, agriculture, coastal cities, and plant and animal species if no action is taken against it.

With these assumptions in mind, please read the following forecast with an open mind.

Mexico on the edge

We start with Mexico, as its fate will become much more intertwined with that of the US over the coming decades. By the 2040s, a number of climate-induced trends and events will occur to destabilize the country and push it to the edge of becoming a failed state.

Food and water

As the climate warms, much of Mexico's rivers will thin out, as will its annual rainfall. This scenario will lead to a severe and permanent drought that will cripple the country's domestic food production capacity. As a result, the county will become ever more dependent on grain imports from the US and Canada.

Initially, during the 2030s, this dependency will be supported given Mexico’s inclusion in the United States-Mexico-Canada agreement (USMCA) that grants it preferential prices under the agreement’s agricultural trade provisions. But as Mexico’s economy gradually weakens due to increased US automation reducing the need for outsourced Mexican labor, its ever-increasing deficit spending on agricultural imports may force the country into default. This (alongside other reasons explained below) could jeopardize Mexico’s continued inclusion in the USMCA, as the US and Canada may look for any reason to cut off ties with Mexico, especially as the worst of climate change commences during the 2040s.

Unfortunately, should Mexico be cut off from USMCA’s favorable trade allowances, its access to cheap grain will disappear, impairing the country’s ability to distribute food aid to its citizens. With state funds at an all-time low, it will become increasingly challenging to purchase what little food that remains on the open market, especially as US and Canadian farmers will be incentivized to sell their non-domestic capacity overseas to China.

Displaced citizens

Compounding this worrying scenario is that Mexico’s current population of 131 million is projected to grow to 157 million by 2040. As the food crisis worsens, climate refugees (entire families) will move from the arid countryside and settle into massive squatter camps around the big cities to the north where government aid is more easily accessible. These camps will not just be made up of Mexicans, they will also house climate refugees who have escaped north into Mexico from Central American countries like Guatemala and El Salvador.

A population of this size, living in these conditions, cannot be sustained if Mexico’s government is unable to secure enough food to feed its people. This is when things will fall apart.

Failed state

As the federal government’s ability to provide basic services crumble, so too will its power. Authority will gradually shift to regional cartels and state governors. Both the cartels and the governors, who will each control splintered off segments of the national military, will lock into drawn-out territorial wars, fighting each other for food reserves and other strategic resources.

For most Mexicans looking for a better life, there will only be one option left to them: escape across the border, escape into the United States.

The United States hides inside its shell

The climate pains that Mexico will face in the 2040s will be unevenly felt in the United States as well, where the northern states will fare slightly better than the southern states. But just like Mexico, the US will face a food crunch.

Food and water

As the climate warms, the snow atop the Sierra Nevada and the Rocky Mountains will recede and eventually melt completely. Winter snow will fall as winter rain, running off immediately and leaving the rivers barren in the summer. This melt matters because the rivers these mountain ranges feed are the rivers that flow into California's Central Valley. If these rivers fail, agriculture across the valley, which currently grows half of the US' vegetables, will cease to be viable, thereby cutting one-quarter of the country's food production. Meanwhile, declines in rainfall over the high, grain-growing plains west of the Mississippi will have similar adverse effects on farming in that region, forcing the complete depletion of the Ogallala aquifer.

Fortunately, the northern breadbasket of the US (Ohio, Illinois, Indiana, Michigan, Minnesota, and Wisconsin) will not be as adversely affected thanks to the Great Lakes water reserves. That region, plus the farmable land lying across the edge of the eastern seaboard, will be just enough to feed the country comfortably.

Weather events

Food security aside, the 2040s will see the US experience more violent weather events on account of rising sea levels. The low-lying regions across the eastern seaboard will be the worst affected, with more regularly occurring Hurricane Katrina-type events repeatedly devastating Florida and the entire Chesapeake Bay area.

The damage caused by these events will cost more than any past natural disaster in the US. Early on, the future US president and the federal government will pledge to rebuild devastated regions. But over time, as the same regions continue to be battered by increasingly worse weather events, financial aid will switch from reconstruction efforts to relocation efforts. The US will simply not be able to afford the constant rebuilding efforts.

Likewise, insurance providers will stop offering services in the most climate affected regions. This lack of insurance will lead to an exodus of east coast Americans deciding to move west and north, often at a loss because of their inability to sell their coastal properties. The process will be gradual at first, but a sudden depopulation of southern and eastern states is not out of the question. This process may also see a significant percentage of the American population turn into homeless climate refugees inside their own country.

With so many people pushed to the edge, this time period will also be prime breeding ground for a political revolution, either from the religious right, who fear God’s climate wrath, or from the far left, who advocate for extreme socialist policies to support the fast-growing constituency of unemployed, homeless, and hungry Americans.

United States in the world

Looking outward, the mounting costs of these climate events will impair not only the US national budget but also the country's ability to act militarily overseas. American's will rightly ask why their tax dollars are being spent on overseas wars and humanitarian crises when it could be spent domestically. Moreover, with the private sector's inevitable shift towards vehicles (cars, trucks, planes, etc.) that run on electricity, the US' reason to meddle in the Middle East (oil) will gradually stop being a matter of national security.

These internal pressures have the potential to make the US more risk-averse and inward looking. It will disengage from the Middle East, leaving behind only a few small bases, while maintaining logistical support for Israel. Minor military engagements will continue, but they will be comprised of drone attacks against jihadi organizations, which will be the dominant forces across Iraq, Syria, and Lebanon.

The biggest challenge that might keep the US military active will be China, as it increases its sphere of influence internationally to feed its people and avoid another revolution. This is explored further in the Chinese and Russian forecasts.

The border

No other issue will become as polarizing for the American population as the issue of its border with Mexico.

By 2040, about 20 percent of the US population will be of Hispanic descent. That’s 80,000,000 people. The majority of this population will live in the southern states neighboring the border, states that used to belong to Mexico—Texas, California, Nevada, New Mexico, Arizona, Utah, and others.

When the climate crisis hammers Mexico with hurricanes and permanent droughts, a large portion of the Mexican population, as well as citizens of some South American countries, will look to flee across the border into the United States. And would you blame them?

If you were raising a family in a Mexico that’s struggling through food shortages, street violence, and crumbling government services, you’d almost be irresponsible not to try crossing into the world’s wealthiest country—a country where you’d likely have an existing network of extended family members.

You can probably guess the problem I’m inching toward: Already in 2015, Americans complain about the porous border between Mexico and the southern United States, largely because of the flow of illegal immigrants and drugs. Meanwhile, the southern states quietly keep the border relatively unpoliced to take advantage of the cheap Mexican labor that helps small US businesses profitable. But when the climate refugees’ start crossing the border at a rate of a million per month, panic will explode among the American public.

Of course, Americans will always be sympathetic to the plight of Mexicans from what they see on the news, but the thought of millions crossing the border, overwhelming state food and housing services, won’t be tolerated. With pressure from the southern states, the federal government will use the military to close the border by force, until an expensive and militarized wall is built across the full length of the US/Mexico border. This wall will extend into the sea by way of a massive Navy blockade against climate refugees from Cuba and other Caribbean states, as well as into the air by way of a swarm of surveillance and attack drones patrolling the full length of the wall.

The sad part is that the wall won’t truly stop these refugees until it becomes clear that attempting to cross means certain death. To close a border against millions of climate refugees means quite a few ugly incidents will occur wherein military personnel and automated defense systems will kill scores of Mexicans whose only crime will be desperation and a desire to cross into one of the last few countries with just enough farmable land to feed its people.

The government will attempt to suppress images and video of these incidents, but they’ll leak out, as information tends to do. That’s when you’ll have to ask: How will the 80,000,000 Hispanic Americans (most of whom will be second or third generation legal citizens by the 2040s) feel about their military killing fellow Hispanics, possibly members of their extended family, as they cross the border? Chances are it probably won’t go down very well with them.

Most Hispanic Americans, even second or third generation citizens won’t accept a reality where their government shoots down their relatives at the border. And at 20 percent of the population, the Hispanic community (mainly comprised of Mexican-Americans) will have a huge amount of political and economic sway over the southern states where they will dominate. The community will then vote in scores of Hispanic politicians into elected office. Hispanic governors will lead many southern states. Ultimately, this community will become a powerful lobby, influencing government members at the federal level. Their goal: Close the border on humanitarian grounds.

This gradual rise to power will cause a seismic, us versus them split within the American public—a polarizing reality, one that will cause the fringe on both sides to lash out in violent ways. It won’t be a civil war in the normal sense of the word, but an intractable issue that can’t be solved. In the end, Mexico will regain the land it lost in the Mexican-American War of 1846-48, all without firing a single shot.

Reasons for hope

First, remember that what you’ve just read is only a prediction, not a fact. It’s also a prediction that’s written in 2015. A lot can and will happen between now and the 2040s to address the effects of climate change (many of which will be outlined in the series conclusion). And most important, the predictions outlined above are largely preventable using today’s technology and today’s generation.

To learn more about how climate change may affect other regions of the world or to learn about what can be done to slow and eventually reverse climate change, read our series on climate change via the links below:

WWIII Climate Wars series links

WWIII Climate Wars P1: How 2 percent global warming will lead to world war

WWIII CLIMATE WARS: NARRATIVES

United States and Mexico, a tale of one border: WWIII Climate Wars P2

China, the Revenge of the Yellow Dragon: WWIII Climate Wars P3

Canada and Australia, A Deal Gone Bad: WWIII Climate Wars P4

Europe, Fortress Britain: WWIII Climate Wars P5

Russia, A Birth on a Farm: WWIII Climate Wars P6

India, Waiting for Ghosts: WWIII Climate Wars P7

Middle East, Falling back into the Deserts: WWIII Climate Wars P8

Southeast Asia, Drowning in your Past: WWIII Climate Wars P9

Africa, Defending a Memory: WWIII Climate Wars P10

South America, Revolution: WWIII Climate Wars P11

WWIII CLIMATE WARS: THE GEOPOLITICS OF CLIMATE CHANGE

China, Rise of a New Global Leader: Geopolitics of Climate Change

Canada and Australia, Fortresses of Ice and Fire: Geopolitics of Climate Change

Europe, Rise of the Brutal Regimes: Geopolitics of Climate Change

Russia, the Empire Strikes Back: Geopolitics of Climate Change

India, Famine, and Fiefdoms: Geopolitics of Climate Change

Middle East, Collapse and Radicalization of the Arab World: Geopolitics of Climate Change

Southeast Asia, Collapse of the Tigers: Geopolitics of Climate Change

Africa, Continent of Famine and War: Geopolitics of Climate Change

South America, Continent of Revolution: Geopolitics of Climate Change

WWIII CLIMATE WARS: WHAT CAN BE DONE

Governments and the Global New Deal: The End of the Climate Wars P12