Kudos to Rush for taking on themes of that size. But God, what a creepy vision.
There is unrest in the forest,
There is trouble with the trees,
For the maples want more sunlight
And the oaks ignore their please.
The trouble with the maples,
(And they're quite convinced they're right)
They say the oaks are just too lofty
And they grab up all the light.
But the oaks can't help their feelings
If they like the way they're made.
And they wonder why the maples
Can't be happy in their shade.
There is trouble in the forest,
And the creatures all have fled,
As the maples scream "Oppression!"
And the oaks just shake their heads
So the maples formed a union
And demanded equal rights.
"The oaks are just too greedy;
We will make them give us light."
Now there's no more oak oppression,
For they passed a noble law,
And the trees are all kept equal
By hatchet, axe, and saw.
The first error is that large trees are genetically different than smaller ones. We don't mind this because natural selection is reasonable in nature. But if the metaphor is to extend to humans, we're getting into genetic determinism. Which, given our history brings up the issue of racial inequality. Conservatives won't admit it, but conservatism frequently leads to a racist explanation for inequality.
The second problem is that, disregarding the genetic metaphor and instead viewing it in psychological terms, environment shapes social efficacy. Large "trees" statistically get there because of social advantage. It's not difficult to imagine why the "trees" of the ghetto are much smaller than those of Greenwich. The body of research overwhelmingly pointing towards human development being socially determined is undeniable.
The fundamental conservative objection to this deterministic view is that "all things being equal", man can choose to succeed or fail and society should allow him this freedom. The first thing a conservative will tell you is that there are many examples of men who succeeded despite the odds. As a refutation of determinism, this is incoherent. It is mainly an appeal to lack of data: there are so many variables that go into one's level of success that retracing all of them is very difficult. However, it isn't impossible, and usually one can discover some strong indicators with a little bit of digging. But scientific research isn't about outliers, but finding theories that are predictable. It is simply obvious that a good upbringing is important for life success. The fact that some people succeed or fail despite their environment is indeed intriguing, but hardly a case against good parenting or healthy social institutions.
Lets return to the phrase "all things being equal". Conservatism depends upon this conceit about human nature. It basically assumes that, at 18 years of age (or younger, for some), men are capable of making the same life choices. So whether they succeed or fail, they are ultimately held to the same standard; they are assumed to be operating from the same knowledge base, the same ability to assess situations and attain desired outcomes.
But this is clearly not the case. "All things", as it were, are not "equal". People possess profoundly different levels of self-efficacy. Some of this is no doubt genetic, and owing to personal temperament. But far and away the larger element is an emotional and cognitive disposition honed over a lifetime of environmental experiences. One might conclude as a practical matter that society cannot reasonably alter this dynamic, but this doesn't change the fact that people experience different levels of life success depending on what social environment they have lived within. So it is for the rich man. So it is for the poor man. The only variable that reliably exists outside this construct is pure, dumb luck.
As to what society can do about it, the short answer is a lot. Beginning with the premise that every citizen has an equal right to the pursuit of happiness, if there is some way in which we can create a more egalitarian dynamic we are morally obligated to do so. This has been the underlying philosophy of most of our most cherished institutions: libraries, parks, roads, schools, etc. Of course these things need to be payed for, and it follows from the understanding that man's success is socially dependent that those more successful owe a debt to society relative to what they have been granted. Likewise, those less successful are owed by society a rectification of what they have been denied.
Of course, the details of how this ought to be done are messy; determining how best to adjust for equality gets into the tricky moral business of individual rights and property. What is equitable? How do we achieve it? The simplest answer to the former goes back to our first principle of man's right to pursue happiness. If self-efficacy is all that is needed, then a system of delivering a basic level of it to every man seems reasonable. This is arguably the main purpose of any good social institution. Libraries provide equal access to the world of ideas. Roads provide physical access to the nation. Police, firemen and the military provide security. Universal health care provides the physical health to act. And the most powerful institution, the sheer magnitude of which we are slowly coming to terms with, is public education. It presents the greatest opportunity society has of delivering to every citizen the individual power to determine - to an extent equal to their peers - their own life success.
In the end, if we are to assume that every man has the same objective potential to grow his "tree", then we must take into consideration the structural differences in society that lead men to different outcomes. To the extend that we are able to do so in a humane and moral manner, we must strive toward the creation and maintenance of institutions that deliver on our nation's promise of real liberty for all, the liberty to determine for themselves their own lot in life.