There was a time—a few days ago, actually—when Donald Trump was getting hammered for the seemingly convoluted process of picking a running mate.

Then there was a time when Trump was being panned for the rollout of Mike Pence, and how he spent most of the appearance talking about himself and other subjects.

Then there was the joint “60 Minutes” interview, when Trump drew flak for finishing some of the Indiana governor’s sentences.

But right now here in Cleveland, no one is talking about any of that. And that’s because news has an incredibly short half-life these days. Big stories flash across the sky like meteors, burn incredibly brightly, and disappear beyond the horizon.

That’s in part because of the tsunami of terror and tragedy that has gripped this country, blowing most other news off the screen, until it’s replaced by another burst of gunfire.

The past two weeks have been heartbreaking—and are giving us whiplash.

There was, in rapid succession, the fatal police shooting in Baton Rouge and a second fatal shooting, less than 24 hours later, in suburban St. Paul. And the horrifying massacre of five police officers in Dallas.

Just as we were reeling from all that came the terrible terrorist attack in Nice. And 24 hours later, an attempted coup in Turkey. And on Sunday, just as my show was starting from the convention here, we got word that six police officers had been shot in Baton Rouge, and three of them would die.

The massacre at the gay nightclub in Orlando was just a month ago, but feels like many months ago.

And yet, with Trump’s convention under way, who is still heavily focused on Nice, as awful as that truck attack was?

And who is still heavily focused on Dallas, now that it’s been superseded by Baton Rouge?

This is not only because the media have a notoriously short attention span. It’s because the human brain can only process so much tragedy at any one time.

Perhaps it’s inevitable that the stories bleed together. And then bleed into the political coverage. That’s why Trump made law and order a theme of the convention’s first session last night. And it’s why Hillary Clinton told the NAACP yesterday that “this madness has to stop.”

It’s no secret that the news cycle is now stuck on hyperspeed, that many of us get second-by-second updates on Twitter or Snapchat as we watch stories unfold on television.

I hate the term the new normal, but that is where we are. I hate the notion that we’re becoming less outraged by each attack, on police or on innocent civilians, because we haven’t quite gotten over the one that took place a few days before. But that is where we are.

Howard Kurtz is a Fox News analyst and the host of "MediaBuzz" (Sundays 11 a.m. and 5 p.m. ET). He is the author of five books and is based in Washington. Follow him at @HowardKurtz. Click here for more information on Howard Kurtz.