It appears journalists are headed for a defining moment with President Donald Trump over the right of the press to ask him tough questions in a manner the president considers rude and hostile.

This is how the antipathy between CNN and Trump unfolded Tuesday when the cable network filed a lawsuit against the president, challenging his constitutional authority to revoke reporter Jim Acosta’s White House press pass for his demeanor at an East Room press conference.

The case can only be described as the president versus the enemy of the people.

It is a pejorative tag Trump assigned to Acosta the day after last week's midterm elections -- and one he frequently uses to describe news outlets he perceives as treating him unfairly. It doesn’t matter if they quote him verbatim from his remarks and tweets in seeking to inform the effect of his words and actions.

Acosta and CNN have been a burr under the president’s saddle for some time. But the testiness of the post-election press conference resulted in Trump directing the Secret Service to yank Acosta’s White House credentials.

The initial exchange between Acosta and Trump started quietly enough. Acosta, seated directly in front of the president’s podium, politely raised his hand to ask the first question. Surprisingly, the president called on him.

“Thank you, Mr. President,” said Acosta, quickly standing, microphone in hand and a self-described “challenging” question on his mind about whether Trump saw the caravan of Central American migrants moving slowly toward the U.S. border as an invasion.

Then the sparks flew.

An obviously upset Trump said he considers the caravan an invasion, dismissed as a “hoax” the Russian investigation that was the  subject of another Acosta query, then ignored the CNN reporter’s attempt to  pursue a third question while admonishing Acosta to yield the microphone and sit down.

Acosta persisted, refusing to give up the mic when a young woman intern tried to take it from him, causing Trump to call the CNN reporter a “rude, terrible person” who should not be working for CNN.

Later that evening, when Acosta returned to the White House grounds, the Secret Service denied him entrance, instructing him to turn over the White House press credentials first issued to him in 2013.

Meanwhile, White House Press Secretary Sarah Huckabee Sanders tweeted a doctored video of Acosta appearing to chop down on the intern’s arm when she tried to grab the microphone from him, stating he had “laid hands on her.” That was clearly not the case, and the White House later walked back the accusation.

Nevertheless, Acosta remained banned from the White House grounds for his press conference conduct and refusing to surrender the microphone to the intern. His subsequent request for a temporary pass pending a hearing on the dispute was likewise denied.

Sanders described the CNN lawsuit to regain Acosta’s press pass as grandstanding.

“The White House cannot run an orderly and fair press conference when a reporter acts this way, which is neither appropriate nor professional,” she said in a statement. “The First Amendment is not served when a single reporter, of more than 150 present, attempts to monopolize the floor.”

The First Amendment’s free press clause and the Fifth Amendment’s due process clause are the central points of the CNN lawsuit against Trump, his press advisers and the Secret Service. The cable network claims they protect journalists from retribution by the president without a hearing.

In a written statement, CNN said: “While the suit is specific to CNN and Acosta, this could happen to anyone. If left unchallenged, the actions of the White House would create a dangerous chilling effect for any journalist who covers our elected officials.”

It is the second time anyone could recall a mainstream journalist denied a White House press pass. It last happened in 1966 when Robert Sherrill, Washington correspondent for the Nation magazine, had his credentials revoked by the Secret Service, which conducts background checks on journalists issued White House press passes.

Sherrill didn’t reapply until 1972 for a pass and again got denied by the Secret Service. The ACLU took up his cause this time, suing the Secret Service in federal court, alleging violation of the First and Fifth Amendments.

A Washington, D.C., circuit court judge issued a favorable decision in 1977. By that time, Sherrill said he was no longer interested in covering the White House and didn’t want or need a press pass. He told the New York Times then he had “been in Washington long enough to realize that was the last place to waste your time sitting around for some dumb (expletive) to give a press conference.”

Whatever the outcome of the CNN suit, the consequence will surely harden the strained relationship between President Trump and the press.

Many presidents have held the press in contempt for reporting news they didn’t agree with or found uncomfortable. But few contemporary occupants of the White House have been as publicly combative as Trump.

Bill Ketter is senior vice president of news for CNHI. Contact him at wketter@cnhi.com.