The Fix's Callum Borchers explains the history of the "protective pool" of reporters that traditionally follows the president, and recounts a few times when a protective pool ended up being critical. (Peter Stevenson/The Washington Post)

In three jolting paragraphs on the front page of The Washington Post on March 31, 1981, David Broder reported that President Ronald Reagan had been shot. In the fourth paragraph, Broder delivered a short anecdote that has appeared in Reagan biographies and history books ever since:

On his way into surgery, the president gamely reassured friends: "Don't worry about me. I'll be fine."

A New York Times account of the assassination attempt included a similarly memorable scene:

Shortly before he was wheeled into the operating room, President Reagan looked up at his wife, Nancy, and told her: "Honey, I forgot to duck."

These were more than vivid details. They showed Reagan alert, confident and even humorous, despite his vulnerable state. They reassured Americans that their president would pull through. And their inclusion in the nation's leading newspapers was made possible because the recently-elected Reagan had granted intimate access to reporters.

Since Donald Trump won the presidency three weeks ago, journalists have complained about the billionaire's unwillingness to implement what is known as a "protective" press pool — a rotating group of reporters that would shadow his every movement, much like they did with Reagan -- and every subsequent president. Trump spokeswoman Hope Hicks has told reporters that they will ultimately have "all of the access that they have ever had under any president," yet the president-elect still won't allow them to travel with him on the same airplane (and never did during the entirety of the 2016 campaign).

On a couple of occasions, journalists have not even been told where Trump is. More than a dozen journalism organizations sent Trump a joint letter on Nov. 16, asking him to uphold a protective pool standard they traced all the way back to Franklin Roosevelt's administration.

Unless you are one of the reporters getting stiff-armed by Trump's transition team, the media's push for more access can seem intrusive and, frankly, unimportant. Why does it matter if Trump goes out to dinner without informing his press corps?

The answer is it doesn't -- almost all of the time. But the protective pool's job isn't to eavesdrop on dinnertime conversations (no one expects that much access). Its job is to be in the vicinity in case of an emergency.

When John F. Kennedy was shot while riding in a car in Dallas in 1963, reporters were in the motorcade and quickly informed the public of the president's status. UPI White House correspondent Merriman Smith wrote the next day that he "had radioed the Dallas bureau of UPI that three shots had been fired at the Kennedy motorcade." The press car followed the Kennedy car to Parkland Hospital, enabling Smith to record this scene:

We skidded around a sharp left turn and spilled out of the pool car as it entered the hospital driveway.

I ran to the side of the bubble-top.

The president was face-down on the back seat. Mrs. Kennedy made a cradle of her arms around the president's head and bent over him as if she were whispering to him.

[Texas] Gov. [John] Connally was on his back on the floor of the car, his head and shoulders resting on the arm of his wife, Nellie, who kept shaking her head and shaking with dry sobs. Blood oozed from the front of the governor's suit. I could not see the president's wound. But I could see blood spattered around the interior of the rear seat and a dark stain spreading down the right side of the president's dark gray suit. ...

Seeing the bloody scene in the rear of the car at the hospital entrance, I knew I had to get to a telephone immediately.

Clint Hill, the Secret Service agent in charge of the detail assigned to Mrs. Kennedy, was leaning over into the rear of the car.

"How badly was he hit, Clint?" I asked.

"He's dead," Hill replied curtly.

On the morning of Sept. 11, 2001, reporters were with President George W. Bush at an elementary school in Sarasota, Fla., when he received word that the World Trade Center had been struck. They joined the president when he flew on Air Force One to Barksdale Air Force Base in Louisiana, and even when Bush's traveling party had to be cut before another flight two hours later, five journalists remained with him.

The access allowed journalists to report from the air that Bush was safe and returning to Washington, where he would address the nation from the Oval Office.

Was it critically important that reporters be permitted to shadow Bush while he read books to elementary school students in Florida? It might not have seemed like it, but journalists' presence became important when disaster unexpectedly struck.

That is what the protective pool is really for — not for the vast majority of days when the president's schedule goes according to plan but for the momentous few when it doesn't.