When a van plowed into a crowd in Barcelona on Thursday, killing at least 14 and injuring scores of others, Fox News quickly pivoted to wall-to-wall coverage of the latest terrorist attack. Their shift was typical of how cable news channels have covered breaking news about similar events, such as last summer's vehicular rampage in Nice, France.

But CNN and MSNBC continued to focus primarily on Charlottesville-related headlines, while also bringing viewers the latest news from Spain.

The pattern extended into Friday morning. CNN's “New Day” led off with Barcelona news and did so at the top of each hour, but it devoted most of its discussion time to topics such as ongoing criticism of President Trump's response to last weekend's violence in Virginia and his defense of confederate statues. MSNBC's “Morning Joe” unfolded in much the same way.

Virtually all of “Fox & Friends,” however, centered on Barcelona and the broader threat of Islamic extremism. When the show did turn to domestic affairs, it was to highlight the elevated security level in Times Square on Friday.

The networks' contrasting coverage priorities show, once again, how easy it is for voters to insulate themselves in bubbles that validate their worldviews. If you think Trump's handling of Charlottesville was just fine and believe the media should drop it, watch Fox News. If you think the president emboldened white supremacists and believe he deserves every degree of heat he is taking, tune to CNN or MSNBC.

Also: If you think Fox News does everything it can to shield Trump, then its undivided attention on Barcelona will reinforce that perception. And if you think the other networks are obsessed with bashing the president, then their less-extensive coverage of Barcelona will serve as evidence.

In a bit of a twist, the New York Times on Thursday obtained a Charlottesville-themed email sent earlier in the day by James Murdoch, chief executive of 21st Century Fox, Fox News's parent company. Here's an excerpt:

It has not been my habit to widely offer running commentary on current affairs, nor to presume to weigh in on the events of a given day save those that might be of particular or specific concern to 21CF and my colleagues. But what we watched this last week in Charlottesville and the reaction to it by the President of the United States concern all of us as Americans and free people. …

I can’t even believe I have to write this: standing up to Nazis is essential; there are no good Nazis. Or Klansmen, or terrorists. Democrats, Republicans, and others must all agree on this, and it compromises nothing for them to do so.

Murdoch added that he and his wife, Kathryn, will donate $1 million to the Anti-Defamation League.

On the day that Murdoch decided to speak out against Trump, his network decided to move on.

Which approach makes more sense? Ratings aren't everything, but consider this: MSNBC beat Fox News in total-day viewership on Wednesday and was the most-watched cable news network for the first time ever. We'll have to wait to see the numbers for Thursday and Friday, but it appears that there is a demand for tough Charlottesville coverage that Fox News is not meeting.

Or, viewed another way, MSNBC is making a strategic play for eyeballs by filling its air with Trump critiques.

President Trump's news conference on Aug. 15. (David Jorgenson/The Washington Post)