HIGGANUM, Conn. — We may never know what happened between black teenager Michael Brown and white police officer Darren Wilson in Ferguson, Missouri, but if we knew our history with slavery, we would know all that we need to about what happened during their fatal 90-second encounter and its devastating aftermath.

I am 63 years old, a white woman and in the odd and probably fortunate position of having written a newly published book on America’s memory of slavery just at the moment when black anger over continuing racial injustice has captured national attention. Nine years ago, when I spoke about a book I co-wrote on connections to slavery in the antebellum North, anguished audiences asked: Why don’t we know about this?

Now the questions are about Ferguson and the gulf between the way white and black Americans view and experience our justice system. The questions are about rage. There’s a continuum between the questions a decade ago and the ones I hear now.

Slavery in America was not a footnote, not “the sad chapter” of our history but the cornerstone of our making. Three generations of historians have documented the astonishing scope, duration, economic importance and savagery of bondage in America, but this key piece of our past still is not prominent in the narrative of our nation.

In studying 18th-century ships’ logs linking Connecticut and the slave trade, I saw that when we made stolen black labor our national bedrock and created a system where inferiority was identifiable by color, we doomed ourselves to a nation where justice and parity for black people still have not been achieved.

The Connecticut seamen and commanders in these ships’ logs did not regard their suffering African cargo as human. When they shoved them onto the English Caribbean islands, where the captives suffered and died in an agricultural system infamous for its cruelty, notions of kidnap and murder did not cross their minds. These black men, women and children were not seen as innocent people; they were part of a supply-and-demand chain that separated an estimated 12.5 million Africans from their homes and changed a hemisphere.

Several hundred thousand in that involuntary migration came to the American colonies, and their palpable humanity didn’t really pose a problem for most settlers here, either. The most pressing exigency of this brave new world was labor, and these valuable workers were the key to America’s early success. Their stolen, uncompensated labor gave us our running start.

The best and most educated people owned slaves, promulgated its benefits and enjoyed the wealth slavery created – the keeper of my Connecticut logbooks was not an obscure mariner but a Saltonstall and the scion of an aristocratic family.

This comfort level with the omnipresence of human bondage became a cascading series of accepted, pathological untruths: Black people were designed for slavery; they didn’t mind being enslaved; they weren’t really human; and they didn’t recognize degradation and injustice.

Scholar Arna Alexander Bontemps documented the way captives in the South became invisible. Their labor was essential to their captors, but because they were not regarded as human beings, their emotions, their lives and their grief as exiles were not part of the record. They appeared as purchases or as laborers. These one-name possessions appear in many Northern records as well.

By the time of the Civil War, 4 million black people were held in slavery in the U.S. The suffering of those millions – most of whom were born here – has never been adequately addressed and explored by Americans. The emancipation that ended legal slavery did not end racial prejudice, and those Americans who believe that it did need only look at the most recent statistics on African-American poverty, access to education, housing and health care. African-Americans are poorer than they were in 2005.

Americans still have no shared and meaningful body of knowledge about a labor system that held those millions in bondage. The hard question of how a post-Enlightenment nation, founded on principles of personal liberty, became the largest holder of slaves in the Western world is still waiting to be answered.

If as a country we truly understood the extraordinary human catastrophe we created when we became economically dependent on the oppression of black people, if we took this in all its dimensions into our hearts and then our history, we would not be scratching our heads over Ferguson. We would understand exactly why the legacy of enslavement is raging through our cities and begin to do something about it.