At a White House discussion about improving the relationship between police departments and black Americans, President Obama declared that “the moment is here.”

He meant a chance for big change, and that’s the problem. The change he and his allies are achieving is like throwing gasoline on a raging fire.

Consider that at about the same time the nation’s first black president was speaking to police chiefs and prosecutors, a group called Black Lives Matter was denouncing police brutality in Times Square, real and imagined. In another sad coincidence of timing, they marched as the city was mourning the murder of NYPD Officer Randolph Holder, the fourth New York City cop killed in 11 months.

Officer Holder was black, as is his alleged killer, but that mattered not a whit to the protesters. One told Fox News that she hopes Holder’s family “realizes that his life is included in the ‘Black Lives Matter’ slogan.”

“We’re talking about black bodies being persecuted across the world,” she added.

This is nonsense on steroids, yet these are the president’s shock troops. Obama and confidante Valerie Jarrett earlier met with the radicals leading the Black Lives Matter movement and encouraged them to keep going, the group has said.

Obama, at last Thursday’s event, praised the group again while also claiming that “everybody understands that all lives matter. Everybody wants strong, effective law enforcement. Everybody wants their kids to be safe when they are walking across the street. Nobody wants to see police officers who are doing their jobs fairly hurt. Everybody understands it’s a dangerous job.”

His saying so doesn’t make it true. The anti-police movement sweeping urban areas proves that many people actually don’t want strong law enforcement, and don’t have any respect for police work. Many, including those Obama met with, appear to hate all cops.

The police-brutality yarn also hides another issue. It is the documented fact that young black men commit violent crimes far out of proportion to their population.

The New York City murder rate is typical. Year in, year out, about 90 percent of homicide victims are nonwhite males, as are 90 percent of their killers.

Yes, there are bad cops, and they come in all races. But for the president to emphasize that there are brutal and racist cops, presumably white, without citing the staggering rate of black-on-black crime distorts both problems. It also misses the relationship between them.

The very nature of police work — to go where the crimes are — means cops will have more charged interactions with young black men than with other racial and ethnic groups. Had Obama acknowledged those realities, and spent serious time in his presidency working toward reducing black crime, he would have far more standing to criticize police and prosecutors.

Indeed, he could have, and should have, cited the murder of Officer Holder as an example of the complexity of the issues. An immigrant from Guyana, the 33-year-old Holder came from a family of police officers there and, after five years on the NYPD, had won several awards and aimed to become a detective. The president might have cited Holder’s sacrifice, if only to show he understands how a police shooting strikes at the heart of other cops and society as a whole.

Obama also could have cited Holder’s alleged killer to make another point. Tyrone Howard, 30, is a career criminal who has been arrested 28 times over the last 16 years, including once for the shooting of a 9-year-old boy. Even Mayor de Blasio, who won office by demonizing cops, called Howard “a hardened and violent criminal” who “should not have been on the streets.”

Howard, facing a six-year prison sentence last May for leading a drug gang, was instead sent to a drug-treatment program by overly lenient judges. He was involved in a shootout with gang rivals last Tuesday when Holder and other officers gave chase. As they got close, Howard allegedly turned and killed the cop with a single shot to the head from an illegal handgun.

Facts are stubborn things, but it is probably asking too much for anti-cop bigots to recognize them. Yet for the president of the United States to cheer their movement is more than a mistake. It is another tragic illustration of how Obama is taking America backward.

Add one more to the ‘hill’ of lies

The postmortems on the Benghazi hearing note the emergence of one significant fresh item. It involves Hillary Clinton’s immediate view of the terror attack on Sept. 11, 2012.

“Two of our officers were killed in Benghazi by an Al Queda-like [sic] group,” she wrote to daughter Chelsea that same night, according to an e-mail Republicans released. Other released documents show she drew the same conclusions to a Libyan official and to an Egyptian official the next day.

Yet publicly, Clinton joined the White House chorus claiming the attack was a spontaneous reaction to an anti-Muslim video.

Technically, the new evidence doesn’t break new ground. It merely confirms she is a liar who will say anything to advance her career.

We already knew that, didn’t we?

Albany is guilty, even if Shel isn’t

Most criminal trials are limited to the guilt or acquittal of individual defendants. But some trials are about something far bigger.

The trial of Sheldon Silver will be Exhibit A of the latter. The former speaker of the state Assembly faces federal charges that he illegally used his office to get rich through a pattern of secret payments from two law firms.

But Albany will be on trial, too. The courtroom spectacle, scheduled to start Nov. 2, will shine a spotlight on how money is doled out to special interests and how lawmakers use their jobs to rake in outside income.

Early moves suggest the defense will not deny that Silver, a Democrat, took the official actions charged, or received millions in payments. Rather, the defense appears ready to argue that there was no quid pro quo involved, and thus no crime.

It’s possible that approach will be successful, but even an acquittal could show that Albany is a rigged game. After all, Silver’s actions should be illegal even if they’re not.

The raft of previous convictions of state officials — about three dozen in the last decade — prove that something is fundamentally broken. Not incidentally, Silver’s former Republican counterpart in the state Senate, Dean Skelos, is facing unrelated criminal charges of his own.

The stage is set then for classic showdowns involving high stakes. It’s the stuff of drama and, hopefully, the beginning of the end of a cesspool culture.

Lamar’s drama is made for TV

Call me cynical, but the Lamar Odom saga smells like a plot — a reality-TV plot. He binges on drugs and hookers, his estranged Kardashian wife rushes to his side, he emerges from his coma, they call off the divorce and live happily ever after. Or until they cash the checks.