We had a war with communism that scared a few, then there was the Y2K thing and now some are seeing the end approaching because of the energy crisis that is possibly approaching.

Convinced the planet’s oil supply is dwindling and the world’s economies are heading for a crash, some people around the country are moving onto homesteads, learning to live off their land, conserving fuel and, in some cases, stocking up on guns they expect to use to defend themselves and their supplies from desperate crowds of people who didn’t prepare.

The exact number of people taking such steps is impossible to determine, but anecdotal evidence suggests that the movement has been gaining momentum in the last few years.

These energy survivalists are not leading some sort of green revolution meant to save the planet. Many of them believe it is too late for that, seeing signs in soaring fuel and food prices and a faltering U.S. economy, and are largely focused on saving themselves.

Some are doing it quietly, giving few details of their preparations — afraid that revealing such information as the location of their supplies will endanger themselves and their loved ones. They envision a future in which the nation’s cities will be filled with hungry, desperate refugees forced to go looking for food, shelter and water.

These survivalists believe in “peak oil,” the idea that world oil production is set to hit a high point and then decline. Scientists who support idea say the amount of oil produced in the world each year has already or will soon begin a downward slide, even amid increased demand. But many scientists say such a scenario will be avoided as other sources of energy come in to fill the void.

So it may be time hoard your MREs left over from the last natural disaster.