We’ve seen the doomsday scenarios played out in countless novels and big-budget films: Some calamity strikes, civilization collapses, and only a few stragglers are left to survive against the odds. Their humanity and ingenuity is put to the test, but in the end, our heroes carry the day and lead us to hope that Earth 2.0 will be wiser and kinder than its ill-fated predecessor.

If a real doomsday arrives, though, the results will be less kind. Picture it: Famine. War. Rape. Disease. Wanton murder. Illiteracy. Prostitution.

What might a future look like? What must stout-hearted people do to survive, if the prophecies of those pesky Mayans prove accurate?

Assume a total global catastrophe, like a horrific virus or nuclear event or solar flare that kills 95 percent of the population and eradicates effective government. In the first few days, the struggle is simply to survive the event itself — steering clear of infected people, seeking protection from radioactive fallout, etc. Long-distance communication may well cease; electricity and water probably would stop flowing and gasoline becomes worth its weight in gold. Families would try to connect and people would seek supplies necessary for their short-term survival, even if acquiring them meant looting and pillaging or even killing.

As reality sets in over the next few weeks, though, a few things would likely happen:

• The elderly and infirm would die.
• Small children would be at elevated risk, especially if their parents died.
• More and more aggressive, Type A folks would seek to dominate the supply chain around them, forming the nexus of small chieftains that would rule over areas not already divided along tribal lines.
• Society would fragment along ethnic/tribal/familial lines in areas where those traditions still carry weight. People would have to increasingly make tough choices to survive, in the “If you want bread, give me your 15-year-old daughter for the night” vein.

In the unfolding months and years, a pseudo-medieval system of the strong controlling the weak would prevail. Most durable resources like transport, weapons and tools become prized objects, typically looted from “before the fall.” Odds are likely that a patchwork of communities would arise across the world. In places where a strong local community exists — think Africa and the Middle East — existing authority structures may well endure. In places like Europe, North America, Russia and China, civilization would fragment along much more strongly Hobbesian lines; picture survivalists with guns offering protection in return for labor, obedience and access to nubile young girls.

But what happens a century later? What happens when the tools break and there’s nothing left to loot? What happens when the bullets and gasoline run out? What happens when the antibiotics and canned food are gone? When the doctors are all dead?

In the Middle Ages, Europe adapted to climate and disease with “more of the same” — a feudal, agrarian society may not have a lot of excess resources, but it could subsist in all but the most horrific of conditions. If modern-day North America collapsed, would enough people remain with the skills necessary to re-create even a feudal level of society? Would we regress from high-tech to agriculture to hunter-gatherer mode? And even if we did farm for a while, who among us could mine or smelt iron or even copper so that we could replace our tools as they wear out and break? Who has sufficient woodworking knowledge to build large structures or sailing vessels? What would happen to literacy? If top-down oppression became the dominant mode of small-unit political organization, how would cooperative villages with a healthy division of labor spring up?

Tough questions. The best a person could do in the early days after the apocalypse is simply survive. After that, all bets are off.

So what prompts this blog post? Merely this: Social fragmentation and happy-go-lucky utopianism remain the hallmark of today’s left-wing ideologies. When push comes to shove, and Occupy fetishists have the chance to live the “we are family” mode of Rousseau-inspired communitarianism, will a post-capitalist, post-apocalyptic world be happier and more free? Or will it look like Europe in the Dark Ages?

Think about what it would be like to survive the apocalypse. Think about what your ideology says about human nature. Then try to reconcile the cognitive dissonance.