The modern American Left and Right in America present a curious picture. Each is blind to a particular aspect of "deep time," which is to say of periods of time longer than personal experience. The Left's blindness is more damaging to their ability to constructively exercise power, but the Right's blindness is more damaging to their ability to understand the larger Universe.
I. The Mistake of the Left
The Left is essentiallly ignorant of cultural "deep time," which is to say of any history outside their personal memories. History and the people in it may be memorized as sets of disconnected data points or used as examples in this or that polemic, but it is not to be understood as a whole, nor lessons drawn from it, nor the opinions of individuals who lived in the past to be judged in the context of their times, let alone taken "seriously" (notice the "dead" part of "dead white males" -- simply having lived long ago is taken as a disqualification of one's arguments!)
The Left aggressively denies the reality of cultural evolution -- namely, that cultural ideas evolve over time through a process of natural selection between competing ideas which are culturally heritable. They do this to the point that "Social Darwinism" (Spencer's misunderstanding of how natural selection applied to human history) is deliberately conflated with the general concept of cultural evolution, and, because Spencer undervalued the importance of cooperation to competition (what we would now term "catallatic competition," or "positive-sum games"), they damn the whole idea that the preservation of customs have any likely relationship to their survival value.
The reasons for this are simple. The first is that the Left is in favor of social engineering as a means of "solving" social problems (indeed, they assume that all social problems are "soluble," even ones arising from the very nature of games or of human beings), and they assume that the conscious planning of the social engineer is necessarily superior to the outcome of cultural-evolutionary forces. This is an easier assumption to make if one denies the existence of cultural-evolutionary forces: if one assumes that the structure of any traditional society is essentially random and hence valueless.
[The sad thing about this is that the existence of cultural evolution does not logically negate the potential value of social engineering. Cultural evolution, just like biological evolution, can get stuck on "local maxima" -- local peaks of fitness on the evolutionary landscape which preclude reaching higer "general maxima" because one would have to make too long a "jump" through a "valley" of lesser fitness. But, just as a genetic engineer would be foolish to alter biology without an understanding of what the original biology was accomplishing, a social engineer is foolish to alter culture without an understanding of what the original society was accomplishing. And the social engineers should be aware that they too are subject to cultural-evolutionary forces, and should be constitutionally restrained from the absolute power needed to engage in rapid social engineering in part for this reason. The 1960's is presented as an obvious example of such error].
The second is that the social engineering schemes of the Left, in part because they ignored historical lessons, themselves represent a strong historical lesson against many of their favored policies. The 20th century is a graveyard littered with tens of millions of literal corpses of those who died before their time in consequence of poorly thought out Leftist social engineering schemes. Many have failed so universally and so completely that, if one admits that history and the outcomes of history have any value at all, they are as unworkable as attempting to fly under Earth gravity and atmosphere by vigorously flapping one's arms unaided, and as dangerous as it would be to jump off a cliff flapping one's arms in the belief that one will thereby soar like an avian.
What this ignorance of cultural deep time and evolution translates into is the "Year Zero" phenomenon, first noted in the French Revolution (where the revolutionaries literally instituted a new calendar in the belief that "everything is different now"). Year Zero generally takes the form of assuming that the current Leftist revolution is so wonderful and special and brilliant that a whole new society is being born in it, one which will determine the whole future of Mankind and which consequently renders all the lessons of the past irrelevant. Those previous thinkers (including Leftist ones!) who expressed ideas incompatible with those of the current revolutionaries are evil or meaningless. Any common-sense concerns with the observed course of the Revolution are swept aside by the utter differentness of the Revolution to earlier societies, and hence the irrelevance of old-fashioned "common-sense" to judging its actions.
This is of course an illusion, and a dangerous one. When we ignore historical lessons, and fail to apply common sense, we may do anything, and large scale random change (as opposed to the selected randomness of evolutionary process) is usually evil or at least pointless, for the same reason that most biological mutations are either lethal or neutral.
In this, though, we see the clue to the fervor with which the Left denies the importance of cultural deep time and evolution. For even a cursory study of history shows that the current Leftist Revolution is strongly analogous to previous Leftist Revolutions, and indeed that all the "new" and "different" policies being urged by this Revolution have in fact been attempted many, many times before, in many different societies, and always with similarly disastrous consequences.
In short, an understanding of history and the reasons why customs survived explodes the illusion which the masters of any Revolution use to keep their followers enthralled, and hence is discouraged by these masters as "anti-social" and "counter-revolutionary." In those countries fortunate enough to be spared the prophets armed, this means dishonest and nasty debating tactics; in the less fortunate countries in which the Revolutionaries take political control, this means firing squads, gulags, and mass starvations.
The consequence of ignoring cultural deep time is that one persistently makes poor policy decisions. Programs will be counterproductive, achieving the opposite of their stated goals, or simply being ignored when not enforced at the point of the bayonet (and even then given only lip-service). Those who ignore history are condemned to repeat it, and those countries who put those who ignore history in power are condemned to suffer damage from the ignorance of their leaders.
II. The Mistake of the Right
The Right is essentially ignorant of biological "deep time," which is to say of anything which occurred before human history. They share that ignorance with the priests who first told and wrote the tales on which our earliest written histories are based, but those priests had the excuse of living in a time before modern Science cast the light of knowledge into the past of our species and its planet. Such wilful blindness is far less excusable in we moderns.
The reason for this, ironically, is that the Right generally is aware of the importance of our traditional customs to our survival and the survival of our society, and they are also aware that these customs are (or at least originally were) grounded in our religious traditions. Now, the Western religious traditions all begin with Creation myths which ascribe relatively recent origins to the Earth and humanity: the Judeo-Christian variety around 4000 BCE, which is not coincidentally roughly the length into the past that an active oral tradition might have enabled the Sumerian and Egyptian priests to know their own history when they began writing it down (around 3000 to 2000 BCE).
[as an aside, if we'd instead gone with the Greek Classical creation myths, the timing of Creation might have been even more recent, as the Greeks started writing down their histories around 500 BCE and consequently their cultural memory extended back to maybe 1500-2500 BCE. This is why Plato has the Egyptians berate the Greeks for being as "babies" -- because the Egyptian written histories extended back beyond the Greek oral ones. So, even a lover of Clssical antiquity such as I have to admit that this would hardly have been a better solution].
Clearly, it would be of use to our cultural stability and survival if the Genesis story were literally true, just as it would be of use to the Leftist social engineering project if the Latest Revolution really did indicate a "Year Zero" in which all previous error would be swept aside and Utopia immediately achieved. And it would be of use to me if I discovered that I actually owned a hundred billion dollars in assets.
However, just because a premise would be useful if true does not make it true. And, sadly (or not), none of the premises to which I adduced are true. I'm not a multi-billionaire. Neither Barack Obama nor Hugo Chavez is about to inaugurate the Millennium. And we have abundant evidence that the Genesis story cannot be literally true, for the Earth is some 4.56 billion years old, making it over a million times older than allowed for in the Bible: and more than 99.999 percent of that time passed before the birth of the first members of the species homo sapiens.
The evidence is of course easy to ignore if one wants to ignore it, because it's scientific, and science requires intellectual effort to understand (just as does history, but at least in history one can apply common sense more directly to the problem). Biological evolution happens very slowly, and within the span of one's own life one is unlikely to see it in any particular macroscopic species which one observes. Geological change is equally slow. Climate change is just fast enough that we can sometimes discern it in our own lives (more so from a diligent reading of history).
The effect of blinding oneself to biological deep time is that one possesses a poor ability to plan strategically over long timescales, and one is correspondingly complacent that favorable conditions will endure. Without an awareness of biological deep time, one does not realize that the Holocene has been a period of mass extinction (because one has no Pleistocene or Pliocene with which to compare), or that we are living in an interglacial series (the Holocene) within a predominantly glacial system (the Quaternary). Without this awareness, the notion that we might tip Earth's climate into a less-convenient mode (in either direction, and the Left is to blame for pretending that global warming is the only way that this could happen) seems unreal.
Conclusion
Thus the Left, blind to cultural deep time, tends to make poor policy decisions where dealing with or managing the human environment are concerned. The Right, blind to biological deep time, tends to make poor policy decisions where dealing with or managing the nonhuman environment is concerned.
This simple formulation is complicated by two factors. The first is that not everyone in a particular division shares his division's blindness -- though the Left tends to be less politically tolerant and thus to enforce blindness more thoroughly on its members than does the Right. At least such is the case right now and in America.
The second is that the Left has one additional problem, which derives in part from its ignorance of history and in particular of the importance, inevitablity, and irreversibility of technological change. They have largely rejected advanced technological engineering solutions to problems, and in consequence limit their ability to solve even environmental problems. So they cannot propose nuclear power to limit global warming, or giant residential towers and hydroponics systems to limit the human footprint on the ecosystem, or (in the long run) expansion into space to limit the human resource demand on the planet.
This was once not so. In the early 20th century, it was Leftists like H. G. Wells who were promoting technological progress and engineering megaprojects as solutions to environmental problems. The Left still does outside Western borders. But the Soviet Union spread anti-technological propaganda through the Western Left in the 1960's through 1980's, and the propaganda became accepted as doctrine. So does the modern Western Left render itself impotent through its slavish adherence to dogma.
The two reason why I am primarily a man of the Right rather than the Left is first: that I believe that success in dealing with the human environment is vital to having the chance to success in dealing with the nonhuman environment; consequently I view the errors of the Left as more severe at least in the short to medium-term. Had America adopted Leftist dogmas in the mid 20th century, we would today be poor and powerless, and nobody would care if we put forth valid solutions to problems in the non-human environment, because nobody follows the lead of a loser. Secondly, the modern Western Left's technophobia renders them irrelevant to the solution of non-human environmental problems: they may have a clearer idea of what's going wrong, but by tossing aside the very tools which would enable them to repair the damage, they deprive themselves of the power to do more than complain about its existence.
But the Right should not be made complacent by this. One needs two eyes to see clearly, and being half-blind is bad, regardless of which side of one's face has been rendered sightless.
Let us, all, begin seeing with both our eyes.