By Conor White

President Trump took his latest shot at the New York Times Friday, calling on Attorney General Jeff Sessions to investigate the publication and find out who wrote the anonymous op-ed that rocked the White House this week.

While the president has threatened to take action, legal experts haven't suggested the Times violated any laws in posting the piece, but the question of whether it should have remains.

"I think it was ethically fine," Margaret Sullivan, Washington Post media columnist and former Public Editor for the New York Times, said Friday in an interview on Cheddar. "I think they do run up against some issues if they also decide to have reporters reveal the identity."

In most newsrooms, the opinion and news sections operate as separate entities. But they may collide if the Times' own reporters begin to dig for answers, Sullivan said.

"This op-ed piece was published by the opinion section, the news section presumably is free to pursue the story, but whether that separation is really going to be honored and be understood is another question."

The paper should prepare for a legal battle, and the author should ready him or herself for the consequences, Sullivan said. After all, it seems Trump is arming himself for war.

"We're looking at it very strongly from a legal point," the president said to reporters before boarding Air Force One on Friday. "We're going to take a look at what he had, what he gave, what he's talking about, also where he is right now."

Trump has called the writer "gutless," and while Sullivan doesn't agree with that sentiment, she acknowledged that the anonymous nature of the piece is something of a detractor.

"If you're going to say something like this that's so negative and so detrimental, it would be much more important to put your name behind it," she said.

The Times only identified the writer as a "senior official". Many of President Trump's advisers, including Mike Pence, Steve Mnuchin, Sarah Huckabee Sanders, Mike Pompeo, and Nikki Haley, have adamantly denied they are behind the piece.

But Sullivan doesn't think the author will be hidden for long.

"I don't think this is going to be a case like Watergate's Deep Throat, where the person, Mark Felt, was a secret for actually decades from almost everyone, I think we're going to know who this person is."

For full interview click here.