Like most progressives, I’ve seen far too many people I otherwise respect talking about how terrible it was that Black Lives Matter protestors have interrupted Bernie Sanders campaign events. “Why make this harder for Bernie? Don’t they want a progressive elected?”

Dana did a good job rounding up perspectives from POC activists and cultural critics that folks should really go read on this. I mean, why ask, “Why?”, when people have been trying to tell you for days? There are plenty of answers if you really want to know.

I’m not in a position to add to any of that analysis, but I can give you some numbers to back up what they’re saying. Even here, though, much of the credit goes to black activists. It wouldn’t have occurred to me to look at these numbers if it weren’t for seeing black reproductive rights activists point out that white women as a group voted for Greg Abbott over Wendy Davis in the last gubernatorial election. (Unfortunately, I don’t remember exactly who at this late date.)

When black people tell you it’s important that Sanders address race issues, they don’t just mean it’s important to them. They don’t just mean it’s a matter of their equality and their very lives, though it is. They mean that it’s important to Sanders or Clinton or whoever it is who ends up the Democrats’ nominee for president next year. Why? Because white people haven’t voted for a Democratic presidential candidate in the last forty years.

Let me repeat that: In the last ten elections, white people as a group have chosen the Republican candidate every single time. No exceptions. The closest they came was in voting for Bill Clinton, where there was only a deficit of 2% of the white voting population, when Perot was splitting the white vote.

The Roper Center at the University of Connecticut has data from exit polling dating back to the 1976 election.* It all shows the same pattern. Black voters are absolutely required for the Democrats to win an election.

“So what”, you say. “Who else are they going to vote for?”

Nobody, according to these statistics. In 1976 through 2000, black people made up 11% to 12% of the U.S. population. They made up only 8% to 9% of the voting population. White people, of course, were continually over-represented in the voting population.

That doesn’t necessarily mean black people disproportionately chose not to vote. There are systemic reasons why a lower percentage of the black population would vote, including laws that disproportionately disenfranchise them and administrative practices that make it harder to vote in poor or urban areas.

However, in 2008, voting demographics shifted. With Barack Obama running, white people and black people were roughly proportionately represented at the ballot box nationally. It made a difference. It added up to roughly an additional 3% of the vote going to Democrats. Just turning out the black vote made that difference.

Now, that doesn’t mean Obama would have lost without those votes. Neither Romney nor McCain/Palin played well to Hispanic voters, and that also makes a difference. Bush would almost certainly have lost in 2000, though, if black voters had been inspired to turn out. There’s a fair chance he would have lost in 2004 as well, though it might have come down to individual states.

Then there’s Jeb Bush. The PACs that be have already declared Bush the 2016 Republican presidential nominee. Clown car notwithstanding, I have little reason to doubt they’ll be able to buy the endorsement. I understand why, as well. He’s one of the most polished and plausible of the Republican candidates. He’ll do just fine among white voters.

This is the same Jeb Bush who has historically done relatively well with Hispanic voters, even better than his brother did running for president.

Right now, we’re looking at either setting him up against a self-proclaimed democratic socialist (yes, I know what a democratic socialist is; what percentage of the voting population do you think does?) or the woman who has been the target of possibly the greatest amount of sexism and misogyny over the course of a single political career. And we’re doing that in the face of several years of laws and administrative rule changes designed to make it harder for Democratic constituencies to vote.

Black voters are going to be hugely important to Democrats in this election. They could well decide it. And they’re ready to turn out over the issue of racialized police brutality.

So next time you think it’s a bad thing for black activists to push Democratic candidates to speak out and speak well on these issues, think about those numbers. How many votes are you willing to see the Democrats squander next year?

* 1976, 1980, 1984, 1988, 1992, 1996, 2000, 2004, 2008, 2012