Darwin is right, of course. If the structure of the society we have built is itself responsible for much or all of the poverty in our country, then we must all share in the blame for the existence of that poverty. And I believe if we are honest we have to admit that our institutions are to blame.
It was not always like this, regardless of what those on the right would like for us to believe. The first organizational structure of society was the tribe. The tribe was created because it gave humans a greater chance to survive in a dangerous world. But the tribe meant sticking together. It meant sharing with and caring for all tribal members, and because of that poverty was non-existent.
But as mankind developed more societal structures, many of those structures began to minimize the tribal value of togetherness and started to value individualism more. This had both a good and a bad effect on the human condition. It allowed individuals to maximize their own potential, but it also allowed some individuals to fall through the cracks of the ever more complex society, creating poverty.
Religion tried at first to address this growing inequality. Almost every religion has helping the poor as one of its base values. But as these religions aged, this became less a value than the propagation of the religion itself (and the rich and powerful became adept at using these religions for their own benefit).
In the United States, we have elevated individualism to one of our highest values. And we adopted an economic system that fits well with that value -- capitalism. But while that system is good for some individuals (those born with the privilege, money, or opportunity to develop the skills necessary for success), it also crushed many individuals (forcing them into a life of poverty and want). There have been efforts at reforming and regulating this capitalism, and this resulted in a fairer society for a while (although it did not go far enough to eliminate poverty).
Unfortunately, we have for the last few decades been going backwards. The right-wing has been able to convince many people in this country that the old way was better -- when there was no regulation on capitalism and the government did very little to help the poor and disadvantaged. They called it "trickle-down" economics -- the belief that if the rich were given more, they would share their greater wealth with the rest of the people in society. It was a stupid idea. They rich, throughout history, have never shared much of their wealth and they don't do it now.
And even though "trickle-down" was a dismal failure that has increased poverty, stagnated worker wages, and created a vast gap between the rich and the rest of America, there are still those who want to continue that policy. We now find ourselves in a situation where most government largesse goes to the rich, and efforts to help the poor (and other hurting Americans) face substantial cuts. We are re-establishing the dog-eat-dog survival of the fittest kind of society that works only for the rich and the privileged, and trying to act like that is a good thing. It is not.
Our tribe is much larger today (comprised of millions instead of a few dozen), but we are still a tribe. Unfortunately, we are a tribe that no longer believes in sharing with and caring for all members of our tribe. That is our great sin -- and it is making us something less than human. We have forgotten that all humans have value, and by forgetting that we are sowing the seeds of our own destruction. No tribe, regardless of its size, can survive by neglecting to provide for all tribe members. Our ancient ancestors knew this, and it is to our eternal shame that we have forgotten that most basic of all values.