It's no secret that America's middle class is in decline. But while we focus on how that decline started (and who is to blame), we often forget to consider what happens if our middle class is wiped out entirely.

If we don't work to restore the American middle class to the vibrant, robust segment of our nation it once was, we may soon witness the end of small-d democracy as we know it. As history and nature both show us, working for the collective good is essential to a functioning democracy, and the natural outcome of that work is a strong and vibrant middle class.

The most ancient form of democracy is found among virtually all indigenous peoples of the world. It's the way humans have lived for more than 150,000 years. There are no rich and no poor among most tribal people: everybody is "middle class." There is also little hierarchy. The concept of chief is one that Europeans brought with them to America, which in large part is what produced so much confusion in the 1600s and 1700s as most Native American tribes would never delegate absolute authority to any one person to sign a treaty. Instead decisions were made by consensus in these most ancient cauldrons of democracy.

The Founders of this nation, and the framers of our Constitution were heavily influenced and inspired by the democracy they saw all around them. Much of the U.S. Constitution is based on the Iroquois Confederacy: the five (later six) tribes who occupied territories from New England to the edge of the Midwest. It was a democracy with elected representatives, an upper and lower house, and a supreme court (made up entirely of women, who held final say in five of the six tribes).

As Benjamin Franklin noted to his contemporaries at the Constitutional Convention: "It would be a very strange thing if Six Nations of Ignorant Savages should be capable of forming a Scheme for such an Union and be able to execute it in such a manner, as that it has subsisted Ages, and appears indissoluble, and yet a like union should be impracticable for ten or a dozen English colonies."

The framers modeled the oldest democracies, and the oldest forms of the middle class, and thus helped create the truly widespread and strong first middle class in the history of modern civilization. That first American middle class was a far cry from the 1950s stereotype that is often referenced in discussions of the ideal middle-income lifestyle.

During our nation's early history, “middle class” was much closer to what we consider today as “working class,” and it was only open to the white, male population. But that early middle class was still a distinct and separate segment of the population from the ruling elites who held great fortunes or the servant class who were considered nothing more than property. For the first time in modern history, that middle group of individuals had a voice and power, and they helped shape our young democracy.

Back in Europe, however, the sort of democracy the framers were borrowing and inventing, and even the existence of a middle class itself, was considered unnatural. For most of the 7,000 years of recorded human history, all the way back to the Gilgamesh Epic, the oldest written story, what we call a middle class is virtually unheard of—as was democracy. Throughout most of the history of what we call civilization, an unrestrained economy and the idea of hierarchical social organization has always produced a small ruling elite and a large number of nearly impoverished workers.

Up until the founding of America, the middle class was considered unnatural by many political philosophers. Thomas Hobbes wrote in his 1651 magnum opus Leviathan that the world was better off with the rule of the few over the many, even if that meant that the many were impoverished. Without a strong and iron-fisted ruler, Hobbes wrote, there would be "no place for industry…no arts, no letters, no society." Because Hobbes believed that ordinary people couldn't govern themselves, he believed that most people would be happy to exchange personal freedom and economic opportunity for the ability to live in safety and security. For the working class to have both freedom and security, Hobbes suggested, was impossible.

Our nation's Founders disagreed. They believed in the rights of ordinary people to self-determination, so they created a form of government in which We the People rule. They declared that all people, not just the elite, have the right to "life, liberty, and the pursuit of happiness." (In that declaration, Thomas Jefferson replaced John Locke's famous "life, liberty, and property" with "life, liberty, and happiness"—the first time the word had ever appeared in the founding document of any nation.) They believed that the people could create a country founded on personal freedom and economic opportunity for all. The Founders believed in the power of a middle class; and in defiance of Hobbes and the conventional wisdom of Europe, they believed democracy and a middle class were the "natural state of man."

As John Quincy Adams argued before the Supreme Court in 1841 on behalf of freeing rebelling slaves in the Amistad case, he stood before and pointed to a copy of the Declaration of Independence:

That DECLARATION says that every man is "endowed by his Creator with certain inalienable rights," and that "among these are life, liberty, and the pursuit of happiness"….I will not here discuss the right or the rights of slavery, but I say that the doctrine of Hobbes, that War is the natural state of man, has for ages been exploded, as equally disclaimed and rejected by the philosopher and the Christian. That it is utterly incompatible with any theory of human rights, and especially with the rights which the Declaration of Independence proclaims as self-evident truths.

As he had so many times before, John Qunicy Adams used his oral arguments in the Amistad case to insert the word “slavery” into a discussion. He believed so strongly in personal freedom and economic opportunity for all that he went back to Congress for another eight years after his term as president just to help overturn the so-called "Gag Rule" which automatically “tabled,” or postponed any anti-slavery legislation without it ever even being heard.

While it would be years before that law was overturned and decades before the Emancipation Proclamation, John Qunicy Adams recognized that our strength as a nation came from our democracy, and that the strength of our democracy came from individual freedom and opportunity.

In a letter to James Loyd in October of 1822, he wrote, “Individual liberty is individual power, and as the power of a community is a mass compounded of individual powers, the nation which enjoys the most freedom must necessarily be in proportion to its numbers the most powerful nation.”

In other words, he recognized Hobbes was wrong, and that the “natural state of man” gave him a voice and the power to use it.

It turns out that the Founders knew something Hobbes didn't: political democracy and an economic middle class is the natural state of humankind. Indeed, it's the natural state of the entire animal kingdom. Biologists used to think animal societies were ruled by alpha males. Recent studies have found that while it's true alpha males (and females, in some species) have the advantage in courtship rituals, that's where their power ends. Biologists Tim Roper and L. Conradt discovered that animals don't follow a leader, but instead move together.

James Randerson did a followup study with red deer to prove the point. How does a herd of deer decide it's time to stop grazing and go toward the watering hole? As they're grazing, various deer point their bodies in seemingly random directions, until it comes time to go drink. Then individuals begin to graze while facing one of several watering holes. When a majority of deer are pointing toward one particular watering hole, they all move in that direction. Randerson saw instances where the alpha deer was actually one of the last to move toward the hole rather than one of the first.

When I interviewed Tim Roper about his research at the University of Sussex in the United Kingdom, he told me that when his findings were first published, scientists from all over the world called to tell him they were seeing the same thing with their research subjects. Birds flying in flocks aren't following a leader but monitoring the motions of those around them for variations in the flight path; when more than 50 percent have moved in a particular direction—even if it's only a quarter-inch in one direction or another—the entire flock veers off that way. It's the same with fish and even swarms of gnats. Roper said his colleagues were telling him that from ants to gorillas, democracy is the norm among animals.

Just like with indigenous human societies—which have had hundreds of thousands of years of trial and error to work out the best ways to live—democracy is the norm among animals, and (other than for the Darwinian purpose of finding the best mate) hierarchy/kingdom is the rarity.

Thus, we discover, this close relationship between the middle class and democracy is burned into our DNA, along with that of the entire animal kingdom. In a democracy there may be an elite (like the alpha male deer), but they don't rule the others. Instead the group is ruled by the vast middle—what in economic terms we would call a middle class.

A true democracy both produces a middle class and requires a middle class for survival. Like the twin strands of DNA, democracy and the middle class are inextricably intertwined, and to break either is to destroy the viability of both.

In human society as well, to have a democracy we must have a middle class. And to have a true middle class, a majority of the people in a nation must be educated and economically secure and must have full and easy access to real news so they can make informed decisions. Democracy requires that its citizens be able to afford to take care of themselves and their families when they get sick, to afford a decent place to live, to find meaningful and well-paying work, and to anticipate, and enjoy, a secure retirement.

This is the American Dream. It's the America my dad grew up in and the America I grew up in. It's the America that is quickly slipping away from us under the burden of crony capitalism and a political system corrupted by it.

When there is no American Dream, when there is no middle class, there cannot be real democracy. That's why when elections are brought to nations that are in crisis or that don't have a broad, stable, well-educated middle class—such as Egypt, Iraq, Iran, and the Palestinian territories—the result is aristocrats, "strongmen," or theocrats exploiting those elections as a way of gaining decidedly undemocratic power.

America's Founders understood the relationship between the middle class—what Thomas Jefferson called the yeomanry—and democracy. Jefferson's greatest fear for the young American nation was not a new king but a new economic aristocracy. He worried that if a small group of citizens became too wealthy—if America became polarized between the very rich and the very poor—democracy would vanish.

Our democracy depends upon our ability to play referee to the game of business and to protect labor and the public good. It is both our right and our responsibility, Jefferson insisted, to control "overgrown wealth" from becoming "dangerous to the state," which is, so long as we are a democratic republic, We the People.

When wealth is concentrated in the hands of the few and the middle class shrinks to the point where it's no longer a politically potent force, democracy becomes a feudal aristocracy: the rule of the elite. As Franklin D. Roosevelt pointed out in 1936, the rule of the many requires that We the People have a degree of economic as well as political freedom. When We the People are given the opportunity to educate ourselves, earn a living wage, own our own homes, and feel confident that we have good child care, health care and care in our old age—in short, when America has a thriving middle class—America also has a thriving democracy.

It's time to restore that thriving middle class to its former glory. But, we must correct the sins of our past and make certain that economic opportunity in our nation is not reserved solely for the white, male population. We need a middle class that is open to all Americas, so that each of us has the individual freedom and power to participate in the process and shape this country's freedom.

If we don't fight for the programs that protect and restore our middle class to its former glory and beyond, we may as well kiss our democracy goodbye.