(CNN) Adding to Ken Burns' legacy of classy historical fare for PBS, "The U.S. and the Holocaust" is documentary filmmaking with a purpose, a three-night production that directly links undercurrents of American society that influenced the decades featured to lingering strains of White supremacy and anti-Semitism. It's fascinating as history, but sobering as current events.
Directed by Burns and frequent collaborators Lynn Novick and Sarah Botstein, the six-plus hours meticulously connect US isolation and xenophobia to the barbarism unfolding in Europe, with historians detailing -- to borrow a well-worn phrase -- what Americans knew, and when they knew it regarding Nazi atrocities.
For President Franklin Roosevelt, humanitarian concerns were surely an issue. Yet they took a back seat to the more pressing fight against Hitler, first in his quiet support for England, and later with America's entry into the war.
Understanding the US's role during the Holocaust requires going back before it, contemplating anti-immigrant sentiment that percolated through the 1920s, auto magnate Henry Ford's virulent anti-Semitism and interest in eugenics and racial superiority. As historian Timothy Snyder notes, Hitler expressed admiration for brutality toward Native-Americans in seizing their lands, seeing it as "The way that racial superiority is supposed to work."
Broken into three chapters, the first encompasses the prewar period, the second 1938-42 and the third the conclusion of the war and its aftermath.
American sympathy toward the Jews only went so far. After the violence of Kristallnacht in 1938 made clear there was little hope for those remaining in Germany, the Congress still rejected a proposal to admit more refugees, including calls to take in 10,000 children per year.
At the same time, the filmmakers detail stories of individual Americans and government officials that endeavored to help Jews escape Nazi persecution, saving thousands of lives.
As is customary with Burns productions (again written by Geoffrey Ward and narrated by Peter Coyote), the deftly curated clips -- such as Charles Lindbergh orating in support of his America First agenda, or footage of the German concentration camps -- get augmented by top actors speaking for key historical figures, with Liam Neeson, Paul Giamatti, Meryl Streep, and German filmmaker Werner Herzog among those lending their voices to the effort.
What really comes through, ultimately, is how complicated the history is -- a mix of heroism and callousness, horror and hope -- and the need to tell these stories, warts and all, at a time when how to teach US history is very much the subject of debate.
"Even though the Holocaust physically took place in Europe, it is a story that Americans have to reckon with too," says historian Rebecca Erbelding.
The filmmakers powerfully bring that message home at the end, incorporating footage of the 2017 Unite the Right rally in Charlottesville, as well as the Jan. 6 insurrection, and the image of a participant wearing a "Camp Auschwitz" sweatshirt.
Addressing such modern examples, historian Nell Irvin Painter speaks of a stream of White supremacy and anti-Semitism that has run through US history. "It's a big stream, and it's always there," she says. "Sometimes it bubbles up, and it shocks us, and it gets slapped down. But the stream is always there."
Few people have done more to make such history commercially viable than Burns, whose expansive contributions to public television -- including more focused projects recently devoted to Benjamin Franklin, Ernest Hemingway and Muhammad Ali -- have continued with astonishing regularity since "The Civil War" in 1990.
While that sort of impact is elusive in this day and age, perhaps foremost, "The U.S. and the Holocaust" (which will be accompanied by a student-outreach program) underscores the importance of chronicling history with all its complexity and messiness. As Snyder puts it, "We have to have a view of our own history that allows us to see what we were."
"The U.S. and the Holocaust" will air September 18, 20 and 21 at 8 p.m. ET on most PBS stations.