"Imagine that the year is 2024. It’s only 15 years in the future but the world has changed a lot. As the flow of hungry ex-farmers from Central America and Southern Mexico turned into a flood in the early 2020s, the US border came under severe pressure and huge new shantytowns sprang up around the crowded Mexican cities. Food riots became a regular feature of urban life and martial law was declared in Mexico City and 10 other big cities. The four big hurricanes of 2023 and the decision to abandon parts of Southern Louisiana and Coastal Florida were the last straw for an American public that had several million of their own climate refugees to resettle inland and public patience with ever growing illegal immigration from Mexico snapped. The White House gave the order to fortify the border and within a week Congress had voted the funds."

"The decision to close the border was a catastrophe for Mexico. The big cities were already a pressure cooker and that shut off the safety valve. The military coup of early 2024 ended Mexican democracy, and by now many shantytowns were effectively no-go zones for the army. Television images of desperate Mexicans being killed while trying to cross the border alienated the one-fifth of the population whose families originally came from Mexico or Central America. After 2024 the United States was an angry and divided society."

"I can tell you how to build a border that will stop any illegal immigrants cold. First you put up razor wire three meters high and you electrify it. Behind that you dig a ditch about three meters deep and ten meters wide and you put your motion detectors down there. Then you build another three-meter-high fence behind that and on top of it you put your video cameras, your floodlights and your remote-controlled machine guns. Maybe you put landmines down in the ditch too. Three thousand kilometers of that kind of fence along the US/Mexican frontier would cost about six months worth of the Iraq War. And now you have built an almost impregnable wall, provided you’re prepared to kill people who try to cross it."

Selected excerpts from Gwynne Dyer's book Climate Wars, which outlines a devastating sequence of future scenarios and issues a wake-up call that's impossible to ignore.

Check out Climate Wars or Dyer's other books at gwynnedyer.com, listen to his Climate Wars feature on CBC Radio or order the book online.