What happened yesterday is incomprehensible.

A Staten Island grand jury voted not to bring criminal charges against NYPD Officer Daniel Pantaleo, who threw his arm around Eric Garner’s neck last summer in what looked much like a departmentally prohibited chokehold.

Garner cried again and again, “I can’t breathe.” Then he was dead.

The disturbing viral video shot by a bystander was an emotional gut punch. It was, and still is, difficult to watch. Video can mislead, of course. But what we thought we saw was bluntly buttressed by New York City’s medical examiner, who said Garner’s death was a homicide resulting from the chokehold and the compression of his chest by police officers.

And now we’re back where we were last week in Ferguson, Missouri, back where we never really left, with a grand jury’s inaction reverberating profoundly and volatilely across the country. And with questions we have been unable to answer — about our nation’s troubled racial history, about the distrust that exists between minorities and police departments, and about why some of us are not treated equally under the law.

Garner was black. Pantaleo is white. Ferguson victim Michael Brown was black; then-police Officer Darren Wilson, who was not indicted by a St. Louis County grand jury, is white.

But the two cases are different. In Ferguson, conflicting testimony and evidence made it impossible to decipher what transpired, and whether Wilson should have felt threatened by Brown.

Garner, on the other hand, did not pose a lethal threat to anyone — not to the police officers who surrounded him, not to bystanders. He was resisting arrest on suspicion of selling “loosies” — individual cigarettes — a very minor allegation.

We wish Staten Island District Attorney Daniel Donovan could step forward to explain why the grand jury declined to bring charges. If there’s a sound legal basis for that decision, we’d like to know it. But state law doesn’t permit him to discuss the salient details. And that lack of clarity leaves us with another crisis of boiling racial anger that must be addressed. Why are people of color treated differently by the police?

“This is an American problem, and not just a black problem,” President Barack Obama said yesterday. “It’s my job as president to help solve it.” He should, and assertively.

The Department of Justice has launched a civil rights investigation into the Garner killing. But we need more. Obama has said he’ll set up a task force to bring more transparency to law enforcement and mend a fractured relationship between police and the communities they protect. That’s a start.

We’ve made great progress over the years, but the past has a long and haunting reach. America’s race problem has taken a serious turn for the worse.

It’s time that we honestly confront it.