From my earliest days, Robert E. Lee felt close at hand. I attended Washington-Lee High School in Arlington, Va., and began my soldier’s life at Lee’s alma mater, the U.S. Military Academy. Today, if Lee still lived in his childhood home in Alexandria, Va., we would be neighbors. So it felt appropriate, when I was a young Army lieutenant, that my wife bought me an inexpensive painting of the famed Southern warrior. And from the wall of the many quarters we occupied over 34 years, Lee’s portrait was literally watching over me. Through the lens of military history and our seemingly parallel lives, he was my hero — brilliant, valiant and loyal.

Outlook • Perspective Illustration by James Steinberg for The Washington Post Stan McChrystal , a retired Army general, is the founder of the McChrystal Group, a leadership advisory firm. He is a co-author, with Jeff Eggers and Jason Mangone, of “Leaders: Myth and Reality.”

As early as his days at West Point, Lee stood out. His classmates nicknamed the studious, near-perfect cadet the “Marble Man.” But over time, even marble’s flaws become more visible.

In the summer of 2017, my wife, Annie, urged me to take down the picture. Disgusted by the images of hate and white supremacy that had descended on Charlottesville in the form of angry, torch-bearing men, she felt that Lee’s picture risked offending guests to our home by sending an unintended message of agreement with the protesters who had sought to preserve a statue of the Marble Man. Initially, I argued that Lee was an example of apolitical loyalty and stoic adherence to duty. But as days passed, I reflected on the way that Lee’s legacy looked to people who hadn’t grown up with my perspective or my privilege. So, on an otherwise unremarkable Sunday morning, I took the painting off the wall and sent it on its way to a local landfill for its final burial. Hardly a hero’s end.

Why did it take me so long to reconsider my thinking on the Marble Man? While I’ve spent my life studying leaders and leadership, abandoning long-held beliefs, some based on comfortable myths, requires a journey that I suspect never ends. Our heroes, in addition to their strengths, almost always harbor profound imperfections. I still admire much about Lee, his integrity included. But to see him as I long had, through a single lens, was to fundamentally misunderstand the kaleidoscopic nature of leaders — and, more broadly, the nature of our past. No matter how much we study or how long we’ve lived, the hardest work we can do is to rotate the kaleidoscope, to see the world in a new light and to evolve our beliefs accordingly.

Such evolution takes time. And for all the years it takes individuals to grapple with their own perspectives, it takes even longer for organizations to follow suit. Institutions are conservative and slow to change, and the military is no exception. Steeped as they are in tradition and admired for consistency, it is difficult for the U.S. armed forces to develop new outlooks on warfare, social issues and, notably, their own view of history.

The way I learned about Lee exemplifies the challenge that service members can face in confronting their biases. For most of my life, I focused on the genius and triumphs of the Marble Man. This was not surprising. No matter where I was living, there seemed to be a statue celebrating Lee’s accomplishments. My elementary school textbooks heralded Lee’s successes on the battlefield. At West Point, he is commonly referred to as the ideal cadet — not just for his lack of demerits, but for his closely held values and his academic achievements. But although the history was well-known, I cannot recall ever debating Lee’s decision to command the Confederate Army against his nation, nor any serious discussion about his attitude toward slavery.

The military prides itself on being apolitical and focused on the moral good. Yet these tenets have also served as an excuse to avoid conversations about contentious or uncomfortable topics, such as race, politics and sexuality. Yes, those are inherently political issues, but military leaders cannot afford to pretend they don’t exist, as the American military is necessarily, and appropriately, a reflection of American society.

The U.S. military plays a major role in shaping our collective memory. In the years after the Civil War and the subsequent Reconstruction, for instance, there was a tacit agreement in the Army (as in much of society) that we wouldn’t treat the South as if it had lost — which is one reason so many Army bases (including Forts Bragg, Benning, Polk, Hood and Lee) are named after Confederate generals. It would be foolish to think that the Army made these decisions unintentionally. Many officers knew full well the signal that these names would send. Whether you revere or revile Confederate soldiers, it’s impossible not to see that their legacy is still with us.

Many Americans face the same problem: We want to be proud of our past, so it’s tempting to look at only the best aspects of it. It’s more comforting to think of Lee as a tragic hero than to try to understand his complex relationship with African Americans today — so we focus on the simpler narrative. Similarly, we perceive the aftermath of Sept. 11, 2001, as a time of unity in the wake of tragedy, ignoring the virulent anti-Muslim fervor that still affects parts of our country. In an effort to remember only the finest of our past, we often present our history as tidier than its reality.

War is often subjected to this tendency to clean up, or at least oversimplify. It is hard to discuss the periodic incompetence, cowardice and criminality that are associated with every military campaign in history without seeming to detract from the very real courage and sacrifice of the vast majority of soldiers. And nothing is more difficult than portraying war in its gritty, brutal reality, or the darker side of soldiers, without the risk of confusing Americans about whether our cause is just or our nation a force for good in the world. As Pericles and others have taught us, we must honor the kinds of service that we seek to have repeated in the future. We must salute and remember the veterans who stepped forward to serve while admitting the complexity of the environment in which they had to operate.

This is the week when we sit down with our families to celebrate our nation’s romanticized notion of Thanksgiving — a version, we know today, that does not reflect the reality of the first celebration of this holiday, in which the bonhomie was a small consolation to indigenous Americans enduring a colonial English conquest.

When we choose how we view history, we risk mythologizing events and people, reducing them to two-dimensional stories. It takes nothing away from Abraham Lincoln’s heroic stewardship of our nation through the Civil War, for instance, to admit that he was still a creature of his era. For most of his career, he saw slaves as rival laborers for white wage-workers and thought they should go back to Africa. Frustratingly, our instinct to sanitize history ensures that we are always looking backward for our better angels, struggling to meet a standard that remains forever out of reach.

There is, in the end, little point in studying a version of history that contains cartoons and monuments rather than real people with nuanced actions and decisions — people whose complexities can teach us about our own. As we come to learn more about our world and ourselves, it is crucial to reexamine our role models and our enemies. There is tremendous value in wrestling with the errors over which history commonly glosses. Coming to terms with the humanity of a leader makes it much more likely that you can be a leader yourself. We are facing a crisis in leadership today — and organizations and individuals both have a role to play in correcting course.

Organizations are often at their finest when they are used as instruments for social change, especially when that change is necessary for the greater good. President Harry S. Truman’s executive order desegregating the military is a magnificent example of how leaders can help speed up institutional change. We are a long way from solving racism in our country, but Truman’s decision was an important step in changing the hearts and minds of our soldiers, their families and society writ large. The same logic can be extended to the inclusion of women in combat and the open service of LGBTQ troops. It’s for these reasons that the military must recast its view of history: The actions of our military leaders have a profound effect on the American psyche — but they cannot make this change alone.

As President John F. Kennedy put it, “The great enemy of truth is very often not the lie — deliberate, contrived and dishonest — but the myth — persistent, persuasive and unrealistic.” We must combat our desire to mythologize our history and our leaders, while retaining our belief in the qualities and ideals those myths often reflect.

[CORRECTION: A previous version of this article incorrectly referred to Washington-Lee High School in Arlington, Va., as “Washington and Lee High School.”]