Of course, the rise of this president has broken bonds on all sides. But for people of color the stakes are different. Imagining we can now be friends across this political line is asking us to ignore our safety and that of our children, to abandon personal regard and self-worth. Only white people can cordon off Mr. Trump’s political meaning, ignore the “unpleasantness” from a position of safety. His election and the year that has followed have fixed the awful thought in my mind too familiar to black Americans: “You can’t trust these people.”

It is not Mr. Trump himself who has done this. Were it not for our reverence for money, Mr. Trump would be easily recognized as the simple-minded, vulgar, bigoted blowhard he is. It is certainly not the neo-Nazis marching on Charlottesville; we have seen their type before. Rather, what has truly broken my heart are the ranks of Mr. Trump’s many allies and apologists.

Mr. Trump’s supporters are practiced at purposeful blindness. That his political life started with denying, without evidence, that Barack Obama is American — that this black man could truly be the legitimate president — is simply ignored. So, too, is his history of housing discrimination, his casual conflation of Muslims with terrorists, his reducing Mexican-Americans to murderers and rapists. All along, his allies have watched racial pornography, describing black America as pathological. Yet they deny that there is any malice whatsoever in his words and actions. And they dismiss any attempt to recognize the danger of his wide-ranging animus as political correctness.

But the deepest rift is with the apologists, the “good” Trump voters, the white people who understand that Mr. Trump says “unfortunate” things but support him because they like what he says on jobs and taxes. They bristle at the accusation that they supported racism, insisting they had to ignore Mr. Trump’s ugliness. Relying on everyday decency as a shield, they are befuddled at the chill that now separates them from black people in their offices and social circles. They protest: Have they ever said anything racist? Don’t they shovel the sidewalk of the new black neighbors? Surely, they say, politics — a single vote — does not mean we can’t be friends.

I do not write this with liberal condescension or glee. My heart is unbearably heavy when I assure you we cannot be friends.

The same is true, unfortunately, of those who hold no quarter for Mr. Trump but insist that black people need to do the reaching out, the moderating, the accommodating. Imagine the white friend during the civil rights era who disliked blacks’ being beaten to death but wished the whole thing would just settle down. However likable, you could not properly describe her as a friend. Sometimes politics makes demands on the soul.

Don’t misunderstand: White Trump supporters and people of color can like one another. But real friendship? Mr. Trump’s bruised ego invents outrageous claims of voter fraud, not caring that this rhetoric was built upon dogs and water hoses set on black children and even today the relentless effort to silence black voices. His macho talk about “law and order” does not keep communities safe and threatens the very bodies of the little boys I love. No amount of shoveled snow makes it all right, and too many imagine they can have it both ways. It is this desperation to reap the rewards of white power without being so much as indicted that James Baldwin recognized as America’s criminal innocence.