starstarstar-halfstar-outline(2.5 stars)

In “Civil War: (Or, Who Do We Think We Are),” filmmaker Rachel Boynton takes viewers on a road trip through American public memory — and thus through ignorance, both accidental and intentional. This high-minded but uneven documentary feels exceptionally well-timed, landing amid local debates and media-created firestorms over such right-wing boogeymen as critical race theory and the 1619 Project: Interviewing teachers, students, Confederate buffs and state politicians, Boynton delves into the abyss dividing Americans in terms of what we know about our own history and how what we know differs by region, self-selection and heritage.

Heritage, it turns out, is a more apt phrase than history for what many citizens are steeped in, especially in the South, where after the Civil War such organizations as the United Daughters of the Confederacy instituted curriculums that forbade teaching that the conflict was waged to preserve slavery. But mythmaking was just as prevalent in the North, where reconciliation was readily and routinely prioritized over racial justice. As the Yale historian David Blight says during a lecture in “Civil War,” a narrative of “mutual valor” was deployed to knit the republic back together — which turned out to be much more convenient than tackling the war’s true causes and consequences.

We’ve been living with the results ever since, in ways that Boynton explores in a film that follows in the peripatetic footsteps of such recent civic-minded travelogues as “American Selfie” and “Our Towns.” At Boston’s prestigious Latin School, an eighth-grade teacher leads her students in a discussion of structural racism to the consternation of a student who steadfastly believes that it’s not as important as individual character. In Mississippi, she interviews a White farmer whose son listens uncomfortably to his story of his ancestors’ oppression during Reconstruction. Echoing several films chronicling the 1921 Tulsa race massacre, “Civil War” examines white supremacist terror that went unpunished and undocumented for decades, in favor of “Old South” images of romance, gentility and moral innocence. In one of the film’s most agonizing scenes, a cemetery holding the graves of enslaved African Americans is literally marginalized alongside a construction site, all but forgotten and desecrated by disuse.

As eloquent as these scenes are, there are moments in “Civil War” when one wishes that Boynton had gone deeper, including with those Boston eighth-graders. During an interview with Mississippi state representative William Shirley, she listens politely as he defends the Confederate battle flag as preserving his history while suggesting that Black people get over theirs — a contradiction she allows to beg for a challenge before disappearing into the ether of lost opportunities. By far the most effective passages of “Civil War” are the moments when she allows her young subjects simply to speak their minds. “I’d rather you not just tell half of my story,” an African American student says at one point. “I’d rather you told the whole story.” A simple request, and a grievously complicated one as well.

TV-MA. Available on Peacock. Contains brief obscenity and violence. 100 minutes.