At the National Prayer Breakfast, President Obama made a statement that you wouldn’t expect to be controversial: violence in the name of religion is a global problem and it’s bad.

He referenced the war in Syria, the killings in Nigeria, anti-Semitism’s resurgence in Europe and religious violence in India. He admitted that it can be hard to “counteract such intolerance. But God compels us to try.” Then he offered a longer thought about humility:

Humanity has been grappling with these questions throughout human history. And lest we get on our high horse and think this is unique to some other place, remember that during the Crusades and the Inquisition, people committed terrible deeds in the name of Christ. In our home country, slavery and Jim Crow all too often was justified in the name of Christ.

The subsequent controversy fuelled by right-wing American commentators and politicians has shown that humility is in short supply.

The response was furious. Right-wing radio and TV talking heads aired long rants about Obama’s “attacks on Christianity”. Jonah Goldberg claimed the Crusades were a justified action against Muslim aggression and the Inquisition was a well-intentioned anti-lynching measure. Ross Douhat spent his morning on Twitter defending conservative Catholicism more generally. Redstate.com’s Erick Erickson declared that Barack Obama was not a Christian in “any meaningful way”. Louisiana Gov. Bobby Jindal argued that since the medieval Christian threat was over a long time ago, we should just focus on combating radical Islam.

Jindal is wrong. While relatively few contemporary Christians are calling for the crusades these days (although crusader iconography is not uncommon in the US military), it’s a mistake to believe in Christian exceptionalism – the idea that Christianity alone has solved its problems – while other religions are still “medieval”. One of history’s lessons is that any ideology, sacred or secular, that divides the world into ‘us versus them’ can and will be used to justify violence.

But when we talk about the past, we’re often really talking about ourselves. In my scholarship, for instance, I look at the ways in which medieval people developed stories about holy war as a response to contemporary problems – which often had little to do with the Crusades.

This kind of tale-telling happens today as well. Matthew Gabriele, a history professor at Virginia Tech, has written about the dangerous nostalgia for the Crusades by right-wing commentators and politicians. In an email, Gabriele told me, “It stems from an understanding of the past as unchanging, one where Christians have always been at war with Muslims and always will be at war with Muslims. It’s an argument that doesn’t care for historical context and one that relies on a false equivalence — either “they” (Muslims) were worse than “us” (Christians) or “they” (Christians of the past) are not “us” (Christians of the present).”

In other words, either the bad stuff done by long-dead Christians has nothing to do with modern Christianity; or maybe the Crusades weren’t so bad for Muslims and Jews after all.

But the Crusades were pretty bad. Historians debate the precise extent and savagery of the violence, but we generally agree that the intensity of the religiously-motivated brutality was staggering. We argue, for example, whether there really was cannibalism during the First Crusade (probably), and whether blood really flowed up to the combatants’ ankles in the Temple of David in 1099 (probably not). But there’s no question that crusaders were sometimes driven to slaughter non-Christian civilian populations both in Europe and in southwest Asia, all in the name of religion.

Obama’s statements therefor reflect well-accepted historical knowledge. The Inquisition led to the execution of many people guilty – at most – of thought crime. Christianity has been regularly and explicitly used to justify colonization, slavery, cultural destruction and racial discrimination. These are simply undisputed facts, and if they make us uncomfortable, it’s worth thinking about why. Moreover, it’s vital to recognize that abolitionists and pacifists, just like those calling for inter-faith harmony today, have drawn strength from their religious convictions.

Reminding the public about ugly moments in the history of Christianity does not make one anti-Christian. To compare the Jordanian pilot who was burned to death by Isis militants to the public burning of Jesse Washington in Waco, Texas does not make one un-American. To acknowledge such comparisons instead gives one the moral authority to call out other acts of violence and atrocity, including those that are justified via religion.

That’s the real message of President Obama’s address at the National Prayer Breakfast. We need humility. We must recognize our fallibility, we must study the past to understand why things happen, and then we must try to do better. History – and not just the one written by the “victors” – is critical for illuminating both our present and our future; how ideologues try to rewrite it reveals the power of the stories we tell about to past to shape the future they hope to construct.