President Donald Trump AP In a speech on Long Island on Friday, President Donald Trump encouraged police to rough up suspects when arresting them.

"Please don't be too nice," he said. "Like when you guys put somebody in the car, and you're protecting their head, you know, the way you put the hand over, like, 'don't hit their head' — and they've just killed somebody — 'don't hit their head.' I said you can take the hand away, OK?"

The uniformed police assembled behind Trump laughed and applauded, and the crowd cheered.

This was gross, and wrong. I also fear, like Matt Yglesias, that this issue is a political winner for Trump.

I think the rising debate over police violence helped fuel the backlash against Democrats among white voters in the north. I think Trump's unconditional defense of the police appealed to them in a way other Republicans' cultural appeals, based in concepts of Christian morality, often did not. And I don't think Trump will face an electoral penalty for comments like this now, any more than he did during the campaign.

So, what to do when a key part of the electorate is wrong?

When I wrote my column urging Democrats to stop being so annoying, and to stop bothering people about their personal life choices, one of the responses I got from several people was, "Is Black Lives Matter annoying?" The broader question was, what if the thing you're annoying people about is really important, and you're right about it? You can't fold on everything for electoral advantage.

And that's right. The increasingly steadfast stances Democrats have taken against police violence and racial disparities in criminal justice probably do annoy a lot of white voters, but they're also substantively very important and worth sticking your neck out to defend.

Chuck Schumer AP

Rather than a policy of "never annoy anybody," my point is that annoyance should pass cost-benefit analysis. You can only annoy people so much and still win, and I think it is just and correct to allocate the Democratic Party "white voter annoyance budget" heavily toward racial justice issues.

But also: If you're going to take the politically costly side of an issue out of principle, you need to find a way to gain a compensating political edge so you can still win elections and implement the politically costly policies you are standing on principle about. You should realize you're annoying some of the voters you might need, and figure out what you can do on some other issue to win some of them over anyway.

I think a lot of the "why Trump won" conversation has involved a false dichotomy. Did Trump win because Democrats lacked a compelling economic agenda, or because Trump found a way to appeal to solidarity among white voters, especially those who did not go to college?

And this has led to a false policy binary: Should Democrats switch to economic messages to try to win those white voters back, or continue to emphasize racial justice to energize and expand their diverse coalition?

This question can only be a binary if Trump voters are single-issue "racial resentment" voters. But they're not — Trump got the electoral edge he needed in the Rust Belt by winning over enough whites who had backed Barack Obama four years earlier.

Democrats don't need to find an accommodation with white voters who like Trump's call for police brutality by becoming soft on police brutality. But as a matter of electoral calculus, they should probably try to find an accommodation with some of these voters on some other issue that might draw them to vote Democratic in spite of Trump's appeal to them on this issue.

Don't say, "The white voters I'd need to win back Pennsylvania are wrong, so what can I do?" Say, "The white voters I'd need to win back Pennsylvania are wrong about this, but I still need to win Pennsylvania, so I'd better find some other issue where I can win them over."

FILE PHOTO: Former U.S. Secretary of State Hillary Clinton takes part in the Women for Women International Luncheon in New York Thomson Reuters

Unfortunately, you may recognize this as roughly what Hillary Clinton was trying to say when she made her infamous "basket of deplorables" comments: that some of Trump's backers could be won over with an appeal to how their lives can be improved.

Clinton made three mistakes: She expressed her campaign strategy out loud; she called a quarter of the electorate "deplorable" and "irredeemable," which they didn't appreciate; and she did not actually have a compelling message for the people she said were turning to Trump because they believed "the government has let them down, the economy has let them down."

But the broader principle is correct: Democrats can have an agenda on racial justice that's more progressive than the opinions of a lot of the white voters they're depending on, so long as they've found another strong way to appeal to those white voters.

And I think Senate Minority Leader Chuck Schumer has hit upon a number of good ideas on the economy that, while obviously not designed just for white voters, could be particularly helpful with some of the white demographics that Democrats have lost ground with in recent elections.

An economic agenda aimed at picking up some of the white voters who have been alienated from the Democratic party is not a substitute for a commitment to racial justice. It's a complement, because only by winning elections will Democrats be able to make progress on either front.