Bernie Sanders thinks America was founded on racist principles. Sean Wilentz, the Pulitzer Prize nominated historian, disagrees. “The myth,” wrote Wilentz in an op-ed published in the New York Times, “that the United States was founded on racial slavery persists, notably among scholars and activists on the left who are rightly angry at America’s racist past.”

So who’s right? Neither. Bernie Sanders’s statement about America’s racist Founding was not a proper argument, nor was it really meant to be. Sanders’s concern is justice today, and whether it is income equality or racial injustice he is targeting, the past is more of a convenient backdrop than a site of serious inquiry. Sean Wilentz’s argument was more substantial, albeit deliberately tendentious. But he is no less wrong than Sanders.

Bernie Sanders made his statement during a speech at Liberty University on Monday last. The spectacle was, frankly, uplifting. After a rousing Christian rock performance and a generous introduction from Liberty University President Jerry Falwell, Jr., Bernie proceeded to be Bernie. Before an ideologically hostile (but exceedingly polite) crowd, he announced his support for a woman’s right to an abortion and gay rights within the first minute of his speech. He went on to condemn the United States as a country brimming with injustices. And he found this injustice historically. “This country was founded way back… on racist principles,” said Bernie, and he quickly added, “and that’s a fact.”

Sean Wilentz’s retort came in the New York Times, where he defended the Constitution as a glorious document of liberty. Wilentz admitted that there were “concessions” to slavery in the Constitution, but called them “consolation prizes.” The “notorious” three-fifths clause was at least better than the southern demand that slaves be counted at five-fifths for the purposes of representation. The slave trade clause (which protected the slave trade from congressional interference until 1808) Wilentz read as a positive—southerners wanted the trade to go on forever, but relented when “antislavery Northerners erupted in protest.” And finally, the fugitive slave clause—a clause that offered slaveholders new protections for their property in the new United States—was “a measure of slavery’s defensiveness” rather than its strength.

Slavery’s defensiveness also explains for Wilentz why southerners came to insist on a proslavery reading of the Constitution. In the face of successful policies of gradual emancipation north of the Mason-Dixon line, slaveholders in the 1830s tried to claim that the Constitution wrote slavery into national law. This was the Constitution of John C. Calhoun, the inveterate vampire of southern rights. In the face of such an ideological tirade, antislavery leaders demanded that the original, antislavery Constitution be restored—a Constitution that confined slavery to state borders and did not recognize it as a national institution.

That’s a nice argument. It was, roughly, the argument of Salmon P. Chase, of Abraham Lincoln, and of Frederick Douglass. These are powerful historical figures for Wilentz to have in his corner. It infuriates professional historians, many of whom have spent the last thirty years teasing out all the ways that slavery has openly, and sometimes less visibly, been helped by constitutional compromises.

Nice arguments are not necessarily good ones. To be fair, Wilentz does not have the room in a 750 word op-ed piece to be sophisticated. He should not lose points for being forceful and direct rather than playing the scholar’s game of endless qualification and nuance. Bernie makes muscular arguments, after all, so why should Wilentz not? Nonetheless, historians who disagree ought to strike at the heart of Wilentz’s argument rather than picking at its edges. Of course the three-fifths compromise was more than a consolation prize, and of course the fugitive slave clause was proactive more than it was defensive. But Wilentz was also right to point out that the slaveholders wanted more at the Constitutional Convention and did not get it. Quibbling over details does not vitiate Wilentz’s argument.

The real answer to Wilentz is to point to one central, yet unarticulated, assumption that underlies his article: the notion that there was one original project and one original essence to the Constitution which should control our interpretation of it. We know this as originalism. Conservative jurists like originalism because it is a constraining principle—it limits what can be done with the Constitution and thus prevents judges (and presumably legislators) from doing pesky things like discovering a right to privacy in the text of the Bill of Rights, or invalidating Jim Crow laws on the basis of the Fourteenth Amendment. Wilentz’s argument more or less picks up this idea—that we can locate an original Constitution that reflects the document’s true nature and that should guide us today.

But this is just not true. In virtually every area that mattered most, the Constitution was forged by debate, compromise, and ambiguity. This is certainly true of slavery. The Constitution protected slavery in critical ways. But it also empowered a national government to take specific actions against slavery in ways that the preceding Articles of Confederation did not. The Constitution gave slaveholders a positive property right to their fugitive servants (read: “slaves”), wherever they might be found in the Union. But it also refused “to admit property in men,” a powerful denial of the very right that the Fugitive Slave Clause guaranteed. The list of ambiguities goes on and on.

The truth of the matter is that the Framers were not thinking in “Antislavery” or “Proslavery” terms. Such labels belong to a much later era. Wilentz correctly identifies the 1830s as the point where such labels became hard and fast—when southerners began insisting upon a proslavery construction of the Constitution, and when abolitionists began formulating an antislavery response. His error is to assume the mantle of the antislavery argument and read it back into 1787.

But if this makes Wilentz wrong, it does not necessarily make Bernie Sanders (or his more sophisticated academic supporters) right. The idea that America was founded on racism is a platitude. Of course it was. But this platitude elides the very real historical presence of a nascent idea of equality before the law, a principle which had real effect during the 1780s. Certainly this principle existed amidst pervasive and systemic racism. The Constitution’s refusal to acknowledge explicitly the legal disabilities of slavery makes it an anomalous document of sorts in its time. But this does not mean it was unimportant. To the contrary—in the face of gross injustice, it is perhaps only the anomaly that matters. That is the only thing that can spark change.

Such a revelation will hopefully lead to a more sober look at our history. Conservatives who want to venerate the Constitution must take seriously the fact that white supremacy girded the Founding generation’s thinking. Liberals must stop trying to pin the nation’s problems on the inequalities of race/class/gender built into the Founding. We would be far better off to admit that we started in an uncertain place and tried to reconcile unimaginable contradictions. The ongoing debate over these contradictions is the actual stuff of our Constitution.

H. Robert Baker teaches history at Georgia State University. He is the author of The Rescue of Joshua Glover: A Fugitive Slave, the Constitution, and the Coming of the Civil War (2007) and Prigg v. Pennsylvania: Slavery, the Supreme Court, and the Ambivalent Constitution (2012). He is currently working on a book about Napa Valley in the 1970s and 80s.