When it comes to the impact of global climate change, we're at a loss for comparison.

Some 14th-century Europeans mistakenly believed that the world was coming to an end as the Black Death killed, by some estimates, 50 percent of the citizens on the continent. And during the 1950s and '60s, nuclear annihilation seemed like a real possibility.

But worst-case climate-change scenarios leave little hope for even a Mad Max-esque, post-nuclear holocaust dystopia. If the climate spirals past certain decisive tipping points, the damage becomes irreversible and doom inevitable. The globe becomes less and less hospitable, until it reaches uninhabitability, a barren cinder.

Maybe it won't be that bad. Nevertheless, even though everyone except inveterate deniers admits the significant potential for disaster, we're doing almost nothing to prevent it.

On Tuesday, President Barack Obama icalled for new regulations on coal-fired power plants. This sounds like progress until you realize that these new regulations are the kinds of half-measures to which Obama is limited by the impossibility of moving meaningful climate-change regulations through Congress.

At best, new regulations will take several years to implement, and they face opposition from Republicans, from business interests, and probably from some Democrats who fear that new regulations will slow down the gradually recovering economy.

Furthermore, last year the Environmental Protection Agency proposed greenhouse gas regulations that would have banned the construction of new coal-fired power plants, probably the dirtiest method of electrical production. The proposal has stalled as the agency considers concerns raised by the power industry. Don't look for significant regulation anytime soon.

A very telling commentary on climate change is the fact that, while a few are still denying that it's real, others are acknowledging that the fight to prevent it is lost and are moving on to proposals of ways to live with it.

The most prominent is probably New York Mayor Michael Bloomberg's proposal to invest $20 billion to protect New York's infrastructure against rising tides and more destructive storms like Hurricane Sandy, which appear to be inevitable. Similar preparations are being developed in other low-lying cities.

The psychological milestone — passing from prevention to adaptation — is worth noting. But what's most interesting is how little our failure to deal with climate change has to do with the science, which is solidly established, and how much it has to do with politics and psychology.

The politics part shouldn't be surprising. Humans are always inclined to use politics to protect their personal interests, and doing so often involves ignoring long-term global concerns in favor of short-term advantages.

It takes some contorted psychology to put such self-interested politics into play. Much of our failure to deal with climate change involves unadorned denial: We like the world as it is, and a significant change in the weather — or in the level of consumption, comfort and pleasure that lies behind climate change — is too horrible to contemplate. So, for the most part, we don't.

Of course, we've noted that people have thought before that the world was going to end in drastic ways. So far, they've been wrong. But we know a lot more about science now than they knew in the 14th century. It's our psychology that hasn't changed much.

And speaking of the end of the world: Einstein said the development of atomic power "changed everything save our modes of thinking, and thus we drift toward unparalleled catastrophe."

Elsewhere, he said that "the solution to this problem lies in the heart of mankind." With regard to climate change, may we find the will to search out the solution. But reasons for optimism are scarce.

----

John M. Crisp teaches in the English Department at Del Mar College in Corpus Christi, Texas.