The day after President Donald Trump was inaugurated, demonstrators descended on Washington to stage what was the largest single-day protest in American history.

Almost exactly three years later, the National Archives Museum has come under fire for altering a photograph of the 2017 Women's March on Washington. In the picture that was prominently featured in an exhibition on women's voting rights, protest signs that read, "God Hates Trump" and "Trump & GOP -- Hands Off Women," were blurred out.

It turns out that the National Archives, whose mission statement touts "openness" as its first principle, edited out anti-Trump statements in order to avoid "current political controversy," according to a spokesperson. The National Archives also initially defended their decision on the grounds that the photograph was for display, rather than being a historical record, but that's a distinction without a difference when it comes to communicating with the public. In fact, an edited public exhibit might have a greater propaganda effect than an altered historical record.

While the National Archives issued an apology and vowed to undergo "a thorough review" of its policies after the Washington Post first reported on the alteration, having discovered it by chance, as a historian I worry about how many other altered documents the Trump administration has buried in our records. Will we ever know?

Censoring photographs to avoid angering a political leader is not a new phenomenon: Stalin's regime famously manipulated photographs to shape public perception. It's all part of what Ruth Ben-Ghiat, a history professor at New York University, calls "memory politics," and the American right has played an ongoing role in shaping our memory in ways that support their goals.