We can almost pinpoint the exact moment on Wednesday when Fox News mostly lost interest in the tragic breaking news out of Des Moines, IA, about two police officers who were killed in separate ambush attacks.

Previously, news of ambush attacks on law enforcement was often treated as a top priority at Fox News, which typically shifted into overdrive in not only devoting time and attention to the senseless killings, but also to instantly assigning political blame, with President Obama often starring as the main villain.

Recall that in July, there were two high-profile attacks on law enforcement: one in Dallas, TX, where five officers were killed when a gunman opened fired on a peaceful protest, and one in Baton Rouge, LA, where three officers were killed.

In both instances, the gunmen were black, and in both instances, Fox News worked overtime assigning partisan blame.

At the time, Fox's Tucker Carlson immediately, and falsely, claimed Obama had routinely labeled police “racist” (he never did) and said that the president had created “an environment where something like this is absolutely inevitable.” The rest of the right-wing media piled on as well: Someone must have radicalized the gunmen, the line of thinking went, and that someone was Obama.

The exact same finger-pointing pattern of relentless politicization played out 10 days later in Louisiana. Following the ambush, “conservative media immediately blamed President Obama, claiming that he has added ‘fuel to the flame of racism,’” Media Matters reported.

And when not casting collective blame on Obama, Fox talkers and other right-wing media commentators targeted Black Lives Matter activists for supposedly cultivating ambush shootings -- shootings that had been denounced by Black Lives Matter leaders.

That’s the background. Now back to the deadly news from Iowa on Wednesday. Fox News appeared to lose interest in the story the moment that law enforcement announced that Scott Michael Greene had been arrested and charged with the deaths of the policemen. Fox News' enthusiasm for the breaking news seems to have flagged not only because Greene is a white man who lives in a house with a Trump-Pence sign out front, but also because the gunman is a racist whose behavior had previously gotten him in trouble with the law.

Just weeks before the killings, Greene was removed by officers from a local high school football game after he started waving around a confederate flag in front of a group of African-American fans.

Following the confrontation, Greene posted a YouTube video depicting the altercation, including his run-in with local police officers who demanded that he leave the game. In a comment below his video, Green wrote that he “was offended by the blacks sitting through our anthem. Thousands more whites fought and died for their freedom.”

Note that social justice activists who have recently begun sitting or kneeling through the national anthem have become the target of withering criticism from Fox News hosts and guests. (Republican presidential nominee Donald Trump has also attacked activists for their national anthem protests.)

Two years earlier, Greene was also arrested after he allegedly threatened to a kill a man and called him the N-word in the parking lot of a local apartment complex.

From The Des Moines Register:

In that incident, Greene was accused of approaching a man in the parking lot and shining a flashlight in his eyes. Greene, who lived in the apartments, called the man the N-word and told the man “I will kill you, (expletive) kill you,” according to the complaint. Greene pleaded guilty to a lesser harassment charge on June 30, 2014, and was sentenced to one year of probation.

So yes, Fox News quickly lost interest in the cop-killing story and covered it only in passing.

Hosting Special Report, Bret Baier gave the ambush story a few sentences on Wednesday night. He provided a skeletal outline and reported that the gunman had “a history of confrontation with police and others.” But Baier didn’t show Greene’s picture, identify him as white, or report on his racist past.

As for the channel’s prime-time lineup of hosts who previously devoted hours and hours to covering ambush police attacks, denouncing the Black Lives Matter movement as a terrorist organization, and blaming Obama for supporting anti-police rhetoric? Those Fox hosts on Wednesday didn’t care about the Iowa ambush story.

The killings actually join the list of other high-profile police attacks that Fox News has had to look away from, for political reasons.

The Associated Press reported that on June 8, 2014, a “man and a woman ambushed two police officers eating lunch at a Las Vegas restaurant, fatally shooting them at point-blank range before fleeing to a nearby Wal-Mart where they killed a third person and then themselves in an apparent suicide pact.” Two months earlier, the killers had traveled to Cliven Bundy's Nevada ranch to join the militia protests against the federal government.

Bill O'Reilly and Sean Hannity both ignored the cop-killer story the night after it happened; Megyn Kelly devoted four sentences to the ambush attack.

Back on September 16, 2014, “survivalist” Eric Frein shot two Pennsylvania state troopers outside their barracks and then disappeared into the Pocono Mountains for weeks. The shooter had a “long-standing grudge against law enforcement and government in general,” according to one law enforcement official. And one friend told CNN that the gunman “was obviously a big critic of the federal government."