“America’s long-standing grand experiment in democracy is being sorely tested,” former President Barack Obama writes in his first opinion piece since leaving the White House, making the urgent case for Democrats to pass voting rights legislation. State laws passed in recent years making it harder to vote, along with aggressive gerrymandering and laws giving partisan state legislatures control over election officials and election certification, represent a “slow unraveling of basic democratic institutions and electoral mechanisms.”

That’s not just happening, either. Someone—a political party—is doing that, and Obama does not pull that punch, as much as even some Democrats would like him to do so. Nor does he shy away from the solution, backing President Joe Biden’s call “to modify Senate rules as necessary to make sure pending voting rights legislation gets called for a vote.”

The stakes, Obama writes, are high. There’s a question of the United States’ role in the world, and a moral one: “We have spilled precious blood and spent countless treasure in defense of democracy and freedom abroad. But as we learned during the Jim Crow era, our role as democracy’s defender isn’t credible when we violate the rights and freedoms of our own citizens. And at a time when democracy is under attack on every continent, we can’t hope to set an example for the world when one of our two major parties seems intent on chipping away at the foundation of our own democracy.”

The strength of the democracy and of voting as a right also has policy effects: “It’s how we can overcome the gridlock and cynicism that’s so prevalent right now. It’s how we can stop climate change, and reform our broken immigration system, and help ensure that our children enjoy an economy that works for everyone and not just the few.”

So what’s to be done? Obama makes it clear that, yes, it’s Democrats who have to do this, because Republicans will not. Sponsors of voting rights bills “have diligently reached out to their Republican colleagues to obtain their support. Sadly, almost every Senate Republican who expressed concern about threats to our democracy in the immediate aftermath of the Jan. 6 insurrection has since been cowed into silence or reversed their positions,” he writes. That’s why modifying the filibuster rules for at least this one issue is a necessity.

Obama takes on the people who claim they are protecting the institution of the Senate by protecting the filibuster, and does so on two grounds. Directly, he points out that “The filibuster has no basis in the Constitution,” and that its use became routine only in recent years. Changing it does not shake the foundations on which the nation rests. But that’s where Obama makes an indirect case that anyone who says they’re protecting the institution, or the norms, is wrong to allow the filibuster to get in the way of passing voting rights legislation: because democracy itself is America’s most important institution. Allowing the filibuster to unravel basic democratic institutions is far more harmful, he argues, than creating another exception to its dominance of the Senate.

Obama also takes on Democratic reticence in another, much subtler way. In his speech on voting rights this week, Biden took an unusually assertive stance—a long overdue, very welcome move—saying, “At consequential moments in history, they present a choice: Do you want to be on the side of Dr. King or George Wallace?  Do you want to be on the side of John Lewis or Bull Connor?  Do you want to be on the side of Abraham Lincoln or Jefferson Davis?” Obama’s op-ed is framed around an invocation of the memory of John Lewis and his fight for voting rights, while he correctly notes that the filibuster was used to bolster Jim Crow. If he’s not as blunt as offering the direct choice between John Lewis and Bull Connor, he nonetheless shows that that is the choice here—an important corrective as some Democrats, like Sen. Dick Durbin, are going squishy, trying to back away from the accurate challenge that Biden may have put into words, but that comes directly from our history.

That is the challenge conservative Democrats like Sens. Joe Manchin and Kyrsten Sinema face. Are they going to be on the side of John Lewis, or are they going to be on the side of the people who cracked Lewis’ skull? No one is accusing Joe Manchin of cracking anyone’s skull, but it’s doing what’s needed to pass voting rights legislation or actively allowing voting rights to be limited in the states. It’s restricting gerrymandering or being complicit in the dismantling of democracy. There is a choice here, and there is a history that shows us what that choice means.